Tropicsweatherpr's WunderBlog 

Good afternoon. An active afternoon is expected in PR,so let's see how it goes.By the weekend,a big increase of showers is expected as a cold front,yes it's April and we are dealing with that moves thru.



AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1120 AM AST THU APR 12 2012

.UPDATE...UPDATED...UNDER THE INFLUENCE OF A SOUTHEAST LOW LEVEL WIND
FLOW...SHOWERS AND A FEW THUNDERSTORMS WILL DEVELOP THIS AFTERNOON
ACROSS NORTH AND NORTHWEST PUERTO RICO. THIS ACTIVITY WILL
LINGER ACROSS THAT AREA OF THE ISLAND UNTIL THE LATE AFTERNOON
HOURS. ELSEWHERE ACROSS THE LOCAL ISLANDS NO SIGNIFICANT
PRECIPITATION IS EXPECTED. SOME LOW LEVEL MOISTURE IS
EXPECTED TO PERSIST ACROSS THE REGION TOMORROW AND THIS MOISTURE IN
COMBINATION WITH DAYTIME HEATING AND LOCAL ISLANDS EFFECTS WILL
PRODUCE A NEW ROUND OF SHOWERS AND THUNDERSTORMS. AN INCREASE IN
MOISTURE IS EXPECTED BY FRIDAY...THUS THE CONVECTION ACTIVITY SHOULD
BE MORE NUMEROUS. A COLD FONT IS FORECAST TO AFFECT THE REGION
BY THE UPCOMING WEEKEND...WITH A NOTICEABLE INCREASE IN CLOUDINESS
AND SHOWERS ACROSS THE FA. A STRONG HIGH PRESSURE WILL BUILD ACROSS
THE LOCAL ISLANDS AFTER THE FROPA...INDUCING A VERY DRY
WEATHER...WINDY CONDITIONS AND COLDER THAN NORMAL TEMPERATURES BY
MONDAY AND TUESDAY NEXT WEEK. PWAT VALUES WILL REMAIN IN THE RANGE
OF 1.40-1.60 INCHES TOMORROW AND THURSDAY...BUT WILL INCREASE TO
AROUND 2.0 INCHES BY LATE FRIDAY AND SATURDAY. ONLY FEW MINOR
CHANGES WERE DONE TO THE PREVIOUS FORECAST PACKAGE.

Wow,90% chance of showers for late Friday and Saturday.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
310 PM AST THU APR 12 2012

.SYNOPSIS...A TROUGH ACROSS THE WESTERN ATLANTIC WILL MOVE EASTWARD
FOR THE NEXT SEVERAL DAYS PUSHING A STRONG COLD FRONT THROUGH THE
AREA SATURDAY NIGHT. THIS FEATURE IS FORECAST TO SETTLE INTO THE
CARI BEAN WATERS ON MONDAY.

&&

.DISCUSSION...AT THIS MOMENT THE DOPPLER RADAR IS SHOWING ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS ALONG THE NORTHERN PORTION
OF THE CORDILLERA CENTRAL. MID TO UPPER LEVEL CONDITIONS ARE
FAVORABLE FOR THIS AND MORE SHOWERS TO DEVELOP ACROSS THE NORTHERN
PORTIONS OF PUERTO RICO THROUGH EARLY EVENING.

AN INCREASE IN MOISTURE IS EXPECTED BY FRIDAY...THUS THE
CONVECTION ACTIVITY SHOULD BE MORE NUMEROUS. A COLD FONT IS
FORECAST TO AFFECT THE REGION BY THE UPCOMING WEEKEND...WITH A
NOTICEABLE INCREASE IN CLOUDINESS AND SHOWERS ACROSS THE FORECAST
AREA. A STRONG HIGH PRESSURE WILL BUILD ACROSS THE LOCAL ISLANDS
AFTER THE FROPA...INDUCING A VERY DRY WEATHER...WINDY
CONDITIONS AND COLDER THAN NORMAL TEMPERATURES BY MONDAY AND
TUESDAY NEXT WEEK. PWAT VALUES WILL REMAIN IN THE RANGE OF
1.40-1.60 INCHES TOMORROW AND THURSDAY...BUT WILL INCREASE TO
AROUND 2.0 INCHES BY LATE FRIDAY AND SATURDAY.

&&

.AVIATION...SHOWERS AND A FEW THUNDERSTORMS WILL CONTINUE OVER THE
NORTH CENTRAL AND NORTHWEST PORTION OF PUERTO RICO...AROUND TJSJ
TJBQ...AND TJMZ. THUS...MTN OBSCURATIONS WILL CONT THROUGH ARND
12/23Z. OTHERWISE VFR IS EXPECTED AT ALL TAF SITES WITH ONLY BRIEF
EXCEPTIONS AT TNCM AND TKPK THROUGH 13/16Z. TJSJ 12/12Z INDICATED A
LIGHT SOUTHEAST WIND FLOW...FROM THE SURFACE TO 12K FEET...BECOMING
WESTERLY AND STRONGER ALOFT.


&&

.MARINE...TRANQUIL MARINE CONDITIONS WILL PREVAIL TROUGH AT LEAST
SATURDAY MORNING. WINDS ARE EXPECTED TO INCREASE SIGNIFICANTLY IN
24 HOURS...THIS IN COMBINATION OF A NNW SWELL WILL GENERATE
HAZARDOUS CONDITIONS THROUGH THE INCOMING WEEKEND.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 74 84 74 82 / 30 30 50 90
STT 76 77 76 77 / 30 30 30 80

Night update confirms the next rain event for Puerto Rico this weekend.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1052 PM AST THU APR 12 2012

.UPDATE...HIGH PRESSURE RIDGE ACROSS THE SOUTHWEST ATLANTIC...AND
AN INDUCED SURFACE TROUGH NOW ACROSS THE MONA PASSAGE WILL SHIFTING
EAST SOUTHEAST TOWARDS THE NORTHEAST CARIBBEAN OVER THE NEXT FEW
DAYS. THIS PATTERN WILL MAINTAIN A FAIRLY LIGHT WIND FLOW ACROSS
THE REGION OVERNIGHT THROUGH FRIDAY...THEN GRADUAL INCREASE OVER
THE UPCOMING WEEKEND AS STRONG HIGH PRESSURE RIDGE WILL BUILD
ACROSS THE WEST AND SOUTHWEST ATLANTIC. IN THE MEANTIME...A
WEAKENING COLD FRONT AND ASSOCIATED BAND OF MOISTURE WILL SLOWLY
SINK SOUTHWARDS OVER THE LOCAL REGION AS PREVIOUSLY MENTIONED.
THIS WILL BRING FAIRLY ACTIVE WEATHER CONDITIONS TO THE LOCAL ISLANDS
AND SURROUNDING WATERS...BEGINNING ON FRIDAY AND CONTINUING OVER THE
UPCOMING WEEKEND. THE PROXIMITY OF THE MID TO UPPER LEVEL TROUGH AND
ASSOCIATED SHORT WAVE PERTURBATIONS WHICH WILL PROPAGATE THROUGH THE
BASE OF THE TROUGH AND JUST NORTH OF THE AREA...WILL ALSO ENHANCE
NOCTURNAL AND DIURNAL CONVECTION EACH DAY AT LEAST UNTIL SUNDAY.
SOME OF THESE SHOWERS AND STORMS WILL CONTINUE TO PRODUCE AREAS
OF LOCALLY HEAVY RAINFALL DURING THE DAYTIME ESPECIALLY ACROSS THE
NORTH AND EAST SECTIONS OF PUERTO RICO...AS WELL AS PARTS OF THE
CULEBRA VIEQUES AND MAINLY THE NORTHERN VIRGIN ISLANDS OVER THE
NEXT 24 TO 36 HOURS...AS THE STEERING WIND FLOW GRADUALLY BECOME
MORE WESTERLY.

Good afternoon. No change to the rain event expected for PR this weekend.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
237 PM AST FRI APR 13 2012

.SYNOPSIS...A MID TO UPPER LEVEL TROUGH ACROSS THE NORTHWEST
ATLANTIC WILL MOVE EASTWARD ACROSS THE CENTRAL ATLANTIC THROUGH THE
NEXT SEVERAL DAYS. AS THIS HAPPENS...A COLD FRONT/SHEAR LINE WILL
MOVE RAPIDLY ACROSS THE LOCAL ISLANDS SATURDAY. AFTER THE FROPA A
DRIER AND STABLE AIR MAS WILL ENCOMPASS THE LOCAL REGION UNTIL AT
LEAST MID WEEK.

&&

.DISCUSSION...LATEST SATELLITE AND RADAR IMAGES THIS AFTERNOON
DEPICTED A SHEAR LINE ASSOCIATED WITH A COLD FRONT JUST ACROSS THE
NORTHWEST AND NORTH ATLANTIC COASTAL WATERS. THIS FEATURE IS
EXPECTED TO PROPAGATE/SINK TO THE SOUTH SOUTHEAST REACHING THE LOCAL
ISLANDS TONIGHT AND SATURDAY AND LASTING POSSIBLE UNTIL EARLY
SUNDAY. AN INCREASE IN CLOUDINESS...SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP ACROSS THE REGION IN ASSOCIATION TO THE PASS
OF THE COLD FRONT. AS THE COLD FRONT APPROACHES...THE LOW LEVEL
WINDS IS EXPECTED TO SHIFT FROM THE NORTHEAST...LATE THIS
AFTERNOON AND THIS EVENING...FOCUSING THE SHOWER ACTIVITY MAINLY
SOUTH OF CORDILLERA CENTRAL. STRONG SURFACE HIGH PRESSURE WILL
THEN BUILD ACROSS THE REGION AFTER THE FROPA...INDUCING A VERY DRY
WEATHER...WINDY CONDITIONS AND COLDER THAN NORMAL TEMPERATURES
SUNDAY...MONDAY AND TUESDAY NEXT WEEK. PWAT VALUES WILL REMAIN IN
THE RANGE OF 1.40-1.60 INCHES THIS EVENING...BUT WILL INCREASE TO
AROUND 2.0 INCHES TONIGHT AND SATURDAY AND DECREASING RAPIDLY
AFTER THAT.

&&

.AVIATION...NMRS SHRA/ISOLATED TSRA WILL CONTINUE TO DEVELOP
ALONG AND SOUTH OF CORDILLERA CENTRAL DURING THE REST OF THE
AFTERNOON AND THIS EVENING...PRODUCING MVFR OR EVEN IFR CONDITIONS
ACROSS TJPS UNTIL AT LEAST 13/23Z. ONLY VCSH ARE EXPECTED ACROSS
THE REST OF THE LOCAL TAF SITES THIS EVENING. SHOWERS THEN
INCREASE IN CVRG OVERNIGHT AND SATURDAY WITH PREDOMINANT MVFR
CIGS AND VSBYS IN MDT RAIN/SHRA AND EVENTUALLY USVI AND NCM SAT
NIGHT. THESE CONDITIONS WILL LIKELY PERSIST THROUGH 12Z SUN AS AN
UNSEASONABLY STRONG CDFNT SWEEPS THROUGH THE LOCAL FLYING AREA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 82 73 81 / 50 90 70 40
STT 75 84 73 84 / 30 80 70 30

The big rain event for Puerto Rico on Saturday and Sunday is imminent as the updated discussion mentions.



AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1011 PM AST FRI APR 13 2012

.UPDATE...INDUCED LOW LEVEL PREFRONTAL TROUGH MOVING ACROSS THE
REGION TODAY...IN COMBINATION WITH MID TO UPPER LEVEL INSTABILITY
AND LOCAL AND DIURNAL EFFECTS...GAVE WAY TO ACTIVE WEATHER CONDITIONS
DURING THE AFTERNOON AND EARLY EVENING HOURS. PERIODS OF LOCALLY HEAVY
RAINFALL ACROSS PARTS OF PUERTO RICO INCLUDING THE SAN JUAN METRO
AREA EVENTUALLY LEAD TO RAPID RIVER RISES...ALONG WITH URBAN AND
SMALL STREAM FLOODING. BY LATE EVENING THE ACTIVITY ACROSS THE
ISLANDS HAD MOVED OFF OR CONTINUED TO DIMINISH. DURING THE REST OF
THE OVERNIGHT HOURS HOWEVER EXPECT SHOWERS AND ISOLATED THUNDERSTORMS
TO DEVELOP JUST AHEAD AND ALONG THE FRONTAL BOUNDARY WHICH WAS NOW
JUST NORTHWEST OF THE FORECAST AREA. EXPECT THE BOUNDARY/SHEAR LINE
TO CONTINUE TO SINK SOUTHWARDS AS PREVIOUSLY MENTIONED AND AFFECT
THE LOCAL ISLANDS AND SURROUNDING WATER OVER THE WEEKEND. THEREFORE
INCREASING CLOUDINESS AND INSTABILITY ALONG WITH ACTIVE WEATHER
CONDITIONS CAN BE EXPECTED ON SATURDAY AND THROUGH SUNDAY. THIS
WILL BE FOLLOWED BY A RAPID IMPROVEMENT IN WEATHER CONDITIONS...AS
STRONG HIGH PRESSURE WITH BUILD ACROSS THE WEST AND SOUTHWEST
ATLANTIC AND USHER COOLER AND STABLE AIR ACROSS THE REGION. THIS
WILL HOWEVER INCREASE THE LOCAL PRESSURE GRADIENT AND THUS
INCREASE THE NORTH NORTHEAST TRADE WINDS.

IN ADDITION...SHORT PERIOD SWELLS WILL BUILD ACROSS THE ATLANTIC WATERS
ON SATURDAY AFTERNOON IN RESPONSE TO THE STRONG WINDS IN THE WAKE OF
THE APPROACHING COLD FRONTAL BOUNDARY. WIND DRIVEN SWELLS WILL QUICKLY
BUILD SATURDAY AFTERNOON... PEAKING EARLY SUNDAY MORNING. THIS WILL
RESULT IN SIGNIFICANT BREAKING WAVE ACTION ON ATLANTIC FACING COASTLINES.
THEREFORE A HIGH SURF ADVISORY WILL BE IN EFFECT FROM SATURDAY AFTERNOON
THROUGH AT LEAST SUNDAY. PLEASE REFER TO THE LATEST COASTAL AND MARINE
HAZARD MESSAGES.

Good morning to all. I have a feeling that flood advisories will be plenty today as the wet 2012 continues for PR.

.HYDROLOGY...RAIN WILL FALL THROUGH THE DAY PRETTY MUCH OVER THE
WHOLE ISLAND AND THE USVI ESPECIALLY LATE TODAY THROUGH MIDNIGHT
TONIGHT. RAINFALL ACCUMULATIONS ARE EXPECTED TO AVERAGE BETWEEN
ONE TO TWO INCHES NORTH OF THE CORDILLERA WITH THE HEAVIEST
AMOUNTS ACROSS NORTHEAST PR. SOUTH OF THE CORDILLERA AMOUNTS WILL
BE GENERALLY LESS THAN ONE INCH. WHILE THERE IS SOME CONCERN FOR
FLOODING ESPECIALLY ACROSS NORTHEAST PR WHERE THE HEAVIEST AMOUNTS
ARE EXPECTED...THESE AMOUNTS ARE EXPECTED TO FALL OVER A 12-HR
PERIOD AT MODERATE INTENSITY. ALSO THE PROGRESSIVE NATURE OF THIS
FRONT ARGUES AGAINST SIGNIFICANT RAINFALL ACCUMULATIONS. WHILE
RISES CAN BE EXPECTED IN SOME OF THE RIVERS IN THOSE AREAS ALREADY
MENTIONED. THE PROB OF FLASH FLOODING SEEMS TOO LOW ATTM TO
WARRANT A FLASH FLOOD OR A FLOOD WATCH. HOWEVER...DO EXPECT TO SEE
SOME STREET FLOODING AND SOME FLOODING IN POOR DRAINAGE AREAS.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1134 AM AST SAT APR 14 2012

.UPDATE...CONSISTENT WITH THE CURRENT FORECAST...SHOWERS DEVELOPED
ACROSS MOST OF PUERTO RICO THIS MORNING. ALTHOUGH THE INTENSITY OF
THESE SHOWERS MAS BEEN MOSTLY MODERATE...THE PERSISTENT SHOWER
ACTIVITY CAUSED URBAN FLOODING IN SOME AREAS ACROSS THE
NORTHWESTERN MUNICIPALITIES OF PUERTO RICO. THE U.S. VIRGIN
ISLANDS HAVE REMAINED FAIRLY DRY WITH ONLY A FEW PASSING SHOWERS
WITH NO SIGNIFICANT ACCUMULATIONS.

DUE TO THE FACT THAT THE WEATHER IS DEVELOPING VERY CLOSE TO THE
CURRENT FORECAST...THERE WAS NO CHANGE IN THE FORECAST.


&&

.AVIATION...MVFR CONDITIONS WILL BE LIKELY AT MOST TAF SITES
TODAY...PARTICULARLY ACROSS PUERTO RICO WHERE SHOWERS AND ISOLATED
THUNDERSTORMS ARE DEVELOPING. TIST...TISX...TNCM...AND TKPK SHOULD
EXPECT PASSING SHOWERS THROUGH THE DAY AND MVFR CEILINGS POSSIBLE
TONIGHT.

Good afternoon. More rain is expected tonight and most of Sunday,but next week looks dry.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
343 PM AST SAT APR 14 2012

.SYNOPSIS...A MID TO UPPER LEVEL TROUGH ACROSS THE WEST CENTRAL
ATLANTIC WILL CONTINUE MOVING EAST TONIGHT THROUGH SUNDAY
MORNING...AND WILL CONTINUE TO PUSH A FRONTAL BOUNDARY ACROSS THE
LOCAL ISLANDS. A MID TO UPPER LEVEL RIDGE IS EXPECTED TO PRODUCE
AN OVERALL DRIER WEATHER PATTERN ACROSS THE LOCAL AREA EARLY NEXT
WEEK.

&&

.DISCUSSION...THE FRONTAL BOUNDARY WILL CONTINUE PUSHING SLOWLY
ACROSS THE LOCAL AREA TONIGHT THROUGH SUNDAY...WITH AN OVERALL
DRIER AND MORE STABLE PATTERN EXPECTED TO ENCOMPASS THE LOCAL
ISLANDS SUNDAY NIGHT AND MONDAY AND PROBABLY CONTINUING THROUGH AT
LEAST TUESDAY AND WEDNESDAY. THROUGH TONIGHT AND MUCH OF SUNDAY...
STILL EXPECT A GOOD DEAL OF CLOUDINESS...SHOWERS AND A FEW
THUNDERSTORMS ACROSS THE LOCAL ISLANDS. ALTHOUGH NOT EXPECTING A
SIGNIFICANT HEAVY RAIN OR FLOOD EVENT AT THIS TIME...PERIODS OF
MODERATE TO HEAVY RAINFALL AND SOME URBAN AND SMALL STREAM
FLOODING WILL OCCUR...AND THERE COULD BE SOME LOCALIZED FLASH AND
RIVER FLOODING.

A GENERALLY FAIR WEATHER PATTERN IS EXPECTED FOR SUNDAY NIGHT AND
MONDAY THROUGH TUESDAY AND WEDNESDAY...BUT WITH INTERVALS OF
CLOUDINESS AND A FEW SHOWERS.

A HIGH SURF ADVISORY GOES INTO EFFECT FOR MOST OF THE ATLANTIC
COASTLINES AT 6 PM THIS EVENING. GIVEN EXPECTED BORDERLINE
CONDITIONS...OPTED TO NOT ISSUE AN NPW FOR WIND ADVISORY AT THIS
TIME. IT CERTAINLY WILL BECOME BREEZY TO WINDY LATER TONIGHT AND
SUNDAY...BUT FEEL IT WILL BE DIFFICULT TO REACH AND MAINTAIN THE
25 MPH OR GREATER SUSTAINED WINDS LOCAL CRITERIA.

&&

.AVIATION...MVFR CONDITIONS ARE LIKELY ACROSS THE PUERTO RICO AND
USVI TAF SITES AS SHOWERS ARE EXPECTED TO AFFECT THESE SITES THIS
EVENING AND TONIGHT...BRIEFLY REDUCING VISIBILITIES AND CAUSING
MVFR CEILINGS. TNCM AND TKPK IS EXPECTED TO REMAIN VFR UNTIL LATE
TONIGHT WITH THE OCCASIONAL PASSING SHOWERS. WINDS ARE EXPECTED
TO INCREASE SIGNIFICANTLY TO 15 TO 22 KNOTS WITH HIGHER GUSTS
TONIGHT THROUGH SUNDAY.

&&

.MARINE...A COLD FRONT WILL CONTINUE MOVING ACROSS THE REST OF
THE LOCAL ATLANTIC AND THEN CARIBBEAN COASTAL WATERS THE REST OF
THIS AFTERNOON THROUGH SUNDAY AND REACH NEAR 17 DEGREES NORTH BY
MONDAY. STRENGTHENING HIGH PRESSURE ACROSS THE ATLANTIC WILL
INCREASE THE WINDS SIGNIFICANTLY TONIGHT THROUGH SUNDAY...WITH
QUICKLY BUILDING SEAS. WINDS AND SEAS WILL BEGIN TO DIMINISH
MONDAY. SMALL CRAFT ADVISORIES ARE IN EFFECT FOR MOST OF THE
LOCAL COASTAL WATERS TONIGHT.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 74 80 72 81 / 90 40 20 20
STT 73 84 73 84 / 90 30 20 20

Good morning. Finnally,the rainy weather is away and drier weather arrives and will stay for most of this week.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
453 AM AST SUN APR 15 2012

.SYNOPSIS...FRONTAL BOUNDARY AND ASSOCIATED MOISTURE WILL CONTINUE
TO MOVE SLOWLY SOUTH AWAY FROM THE LOCAL ISLANDS. A DRIER AND MORE
STABLE WEATHER PATTERN IS EXPECTED TO PREVAIL THROUGH AT LEAST NEXT
THURSDAY.

&&

.DISCUSSION...FRONTAL BOUNDARY AND ASSOCIATED MOISTURE WILL CONTINUE
TO MOVE SLOWLY SOUTH AWAY FROM THE LOCAL ISLANDS. SURFACE HIGH PRESSURE
IS NOW BUILDING ACROSS THE WESTERN ATLANTIC INTO THE LOCAL AREA...
MAINTAINING A TIGHT PRESSURE GRADIENT ACROSS THE LOCAL ISLANDS. WINDS
ARE EXPECTED TO PEAK DURING THE MORNING HOURS BUT NORTH NORTHEAST
WINDS OF 15-20KTS WILL CONTINUE TO PREVAIL THROUGH AT LEAST EARLY
TUESDAY MORNING. A DRIER AND MORE STABLE WEATHER PATTERN WILL PREVAIL
ACROSS THE ISLANDS THROUGH THURSDAY AS AFOREMENTIONED SURFACE HIGH
PRESSURE DOMINATES THE LOCAL WEATHER REGIME. THEREFORE...EXPECT
MOSTLY FAIR WEATHER CONDITIONS AND PARTLY CLOUDY SKIES WITH LIMITED
SHOWER ACTIVITY DURING THE NEXT FOUR DAYS OR SO.

&&

.AVIATION...CDFNT HAS MOVED SOUTH OF SAINT CROIX BUT LOW CIGS WILL
CONTINUE TO IMPACT NORTH COAST PR...USVI AND LEEWARD ISLAND
TERMINALS THROUGH AT LEAST 15Z TODAY WITH QUICK IMPROVEMENT XPCD IN
THE AFTERNOON. WINDS WILL CONTINUE TO BE MAIN PROBLEM WITH WINDS
FROM THE NORTHEAST AT 20G30KT THROUGH MOST OF THE DAY AT ALL
TERMINALS XCPT JPS WHERE LAND FRICTION IS THE GREATEST. MAYAGUEZ AND
ST THOMAS WILL EXPERIENCE GAP AND KATABATIC WINDS RESPECTIVELY WITH
SIGNIFICANTLY HIGHER GUSTS UPWARDS OF 35 KTS THROUGH MOST OF THE
DAY.

&&

.MARINE...EARLIER ASCAT PASS AROUND 0130Z MEASURED SOLID 25-KT
WINDS ACROSS THE MONA PASSAGE AND THE ATLC AND CARIB COASTAL WATERS.
THESE WINDS WILL CONTINUE THROUGH TONIGHT WITH A DIMINISHING TREND
EXPECTED ON MON. BUOYS 41043 AND 41053 HAVE BEEN REPORTING 10 AND 8
FOOT SEAS RESPECTIVELY IN 7-8 SECONDS NNE WIND WAVES AND THESE WILL
CONTINUE THROUGH TONIGHT. WINDS WILL BEGIN TO DIMINISH ON MONDAY AND
SEAS AS WELL. LOWERED SEAS BELOW 7 FT LATE MON NIGHT FASTER THAN
GUIDANCE SUGGESTS AS MARINE MODELS HAVE A TENDENCY/BIAS TO KEEP SEAS
MUCH HIGHER AFTER WINDS SUBSIDE.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 81 74 81 73 / 10 20 20 20
STT 76 74 75 74 / 10 20 20 20

Quoting DDR:
3-5 inches is forecasted for Trinidad starting Tuesday/Wednesday into the weekend.

Good morning. Wow,interesting weather down there. Here in PR,we will be in a dry period for most of this week,with increasing moisture again afterwards.

Good afternoon. It looks like the good weather we have been with will end by the weekend when moisture will increase.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
249 PM AST TUE APR 17 2012

.SYNOPSIS...SURFACE HIGH PRESSURE TO THE NORTHWEST OF THE LOCAL
AREA AND A SURFACE LOW PRESSURE ACROSS THE CENTRAL ATLANTIC IS
CAUSING A TIGHT PRESSURE GRADIENT THAT WILL MAINTAIN MODERATE TO
LOCALLY FRESH WINDS ACROSS THE LOCAL AREA UNTIL WEDNESDAY. THIS
WILL ALSO MAINTAIN A STABLE AIR MASS ACROSS THE AREA...KEEPING THE
WEATHER FAIRLY DRY UNTIL FRIDAY.

&&

.DISCUSSION...WE ARE STILL UNDER THE SAME DRY AND STABLE AIR MASS
THAT IS KEEPING US UNDER FAIR WEATHER PATTERN WITH A MODERATE
BREEZE. 12Z SOUNDING INDICATED ONLY 0.78 INCHES OF PRECIPITABLE
WATER AND FORECAST SOUNDINGS INDICATE THAT THE PRECIPITABLE WATER
OVER THE AREA SHOULD REMAIN AT AROUND 1 INCH OR LOWER UNTIL
FRIDAY. THIS IS DUE BECAUSE THE LOW PRESSURE OVER THE CENTRAL
ATLANTIC IS FORECAST TO WEAKEN AND THEN MOVE NORTHEAST...AT THE SAME
TIME THAT A SURFACE LOW DEVELOPS OVER THE EASTERN UNITED
STATES...BRINGING IN MOISTURE FROM THE SOUTH TO OUR LOCAL AREA.
THERE IS ALSO AN UPPER TROUGH THAT THE GFS MODEL DEVELOPS TO THE
NORTH OF THE AREA FOR THE WEEKEND...WHICH WILL CREATE A BETTER
ENVIRONMENT FOR THE DEVELOPMENT OF SHOWERS AND ISOLATED
THUNDERSTORMS.


&&

.AVIATION...PREVAILING VFR CONDITIONS WILL CONTINUE ACROSS THE LOCAL
ISLANDS AND AT ALL TAF SITES THROUGH THE NEXT 24 HOURS. HOWEVER...
VERY BRIEF MVFR CONDITIONS AND LOCAL MOUNTAIN OBSCURATIONS ARE
POSSIBLE IN ISOLATED PASSING SHOWERS.


&&

.MARINE...PRECAUTIONARY STATEMENTS ARE IN PLACE FOR WINDS OF AT
LEAST 18 KNOTS AND SEAS UP TO 6 FEET. THE SMALL CRAFT ADVISORY FOR
THE OFFSHORE ATLANTIC WATERS WAS ALLOWED TO EXPIRE.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 72 83 74 84 / 20 10 10 10
STT 73 86 74 84 / 20 20 10 10

Good afternoon. It looks like this upcomming weekend will be a wet one once again as plenty of moisture invades PR from the South and Southeast.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
257 PM AST WED APR 18 2012

.SYNOPSIS...AT UPPER LEVELS...A SHORT WAVE TROUGH WILL MOVE
THROUGH TONIGHT AND THE CORE OF AN 80 KNOT JET WILL CROSS THROUGH
THE AREA...FOLLOWED QUICKLY BY A SHORT WAVE RIDGE ON THURSDAY
EVENING. A WEAK TROUGH WITH A JET CORE WILL PASS THROUGH ON
SATURDAY MORNING FOLLOWED BY A WIDE AND RELATIVELY STRONG RIDGE
PASSING THROUGH ON SUNDAY EVENING. A STRONG TROUGH WILL DIG INTO
THE WESTERN CARIBBEAN LATE NEXT WEEK.

AT MID LEVELS...WEAK TROUGHING CONTINUES IN THE AREA UNTIL THE
WEEKEND. A RIDGE WILL FOLLOW THAT WILL CONTINUE INTO MONDAY OF
NEXT WEEK AND THEN EDGE INTO THE WESTERN TROPICAL ATLANTIC DURING
THE REST OF THE WEEK. MOISTURE INCREASES...BEGINNING FRIDAY AND
PEAKING AROUND MID WEEK...BUT STAYS MAINLY OVER THE DOMINICAN
REPUBLIC.

AT LOWER LEVELS...DRY AIR OVER THE WESTERN ATLANTIC ASSOCIATED
WITH A WEAK HIGH PRESSURE WILL MOVE EAST. MOISTURE WILL BEGIN TO
INCREASE ON FRIDAY. MOISTURE FROM SOUTH AMERICA WILL MERGE WITH
MOISTURE IN A EASTWARD MOVING CONVERGENCE ZONE BEGINNING TUESDAY
AND CONTINUING THROUGH THE END OF THE WEEK.

&&

.DISCUSSION...SHOWERS HAVE JUST BEGUN TO FORM IN PARTLY CLOUDY
SKIES THIS AFTERNOON. INTENSE HEATING HAS GENERATED REPORTS OF FIRES IN
MAYAGUEZ AND WHIRLWINDS IN GUAYAMA. FIRES MAY HAVE ALSO BEEN SEEN
IN SALINAS IN SATELLITE IMAGERY. WITH MODEST EAST NORTHEAST
FLOW...SEA BREEZES HAVE BEEN PREDOMINANT OVER MOST COASTAL AREAS.

DRY AIR WILL CONTINUE OVER THE AREA UNTIL FRIDAY WHEN MOISTURE
RETURNS FROM THE SOUTHEAST. FROM FRIDAY TO TUESDAY FLOW CONTINUES
TO HAVE A SOUTHERLY COMPONENT THAT BRINGS INCREASING MOISTURE AND
SHOWERS IN FROM THE SOUTHEAST. AS MOISTURE FILLS IN AT MID AND
UPPER LEVELS SHOWERS WILL BECOME MORE WIDESPREAD AND
STRONGER...ESPECIALLY IN THE WEST AND NORTHWEST PARTS OF PUERTO
RICO DURING THE WEEK NEXT WEEK. AT PRESENT IT LOOKS LIKE MOST OF NEXT
WEEK WILL BE SHOWERY. WITH BETTER DIURNAL HEATING...EXPECT A
GREATER FREQUENCY OF THUNDERSTORMS AS WELL. IT IS TOO EARLY TO SAY
MUCH ABOUT POSSIBLE FLOODING...BUT EXPECT THE BEST MOISTURE TO BE
OVER THE DOMINICAN REPUBLIC RATHER THAN PUERTO RICO OR THE U.S.
VIRGIN ISLANDS.

&&

.AVIATION...VERY BRIEF MVFR CONDITIONS WILL REMAIN POSSIBLE THROUGH
ABOUT 18/22Z OVER SOUTHWEST PUERTO RICO INCLUDING THE VICINITY OF
TJMZ AND TJPS DUE TO ISOLATED TO LOCALLY SCATTERED SHOWERS.ELSEWHERE...
VFR CONDITIONS EXPECTED NEXT 24 HOURS. LOW LEVEL WINDS FROM THE EAST
NORTHEAST AT 10 TO 15 KT.

&&

.MARINE...WINDS AND SEAS WILL DIMINISH...ALTHOUGH WINDS REMAIN
ABOVE 15 KNOTS IN THE SOUTHERN-MOST WATERS SOUTH OF PUERTO RICO
UNTIL FRIDAY. SEAS INCREASE SUNDAY INTO MONDAY BUT SMALL CRAFT
ADVISORIES ARE NOT EXPECTED DURING THE NEXT 7 DAYS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 73 83 74 85 / 0 0 10 10
STT 72 84 74 86 / 0 0 10 10

Quoting DDR:
Good evening
we had some nasty weather today,some flash floods, thunder,3 inches of rain by me,hope it doesn't get that nasty when the trough pulls north on you.

Good evening. Yes,let's see how much rain comes from down there this weekend.

Good afternoon.More wet weather starting this weekend and lasting thru most of next week.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
251 PM AST THU APR 19 2012

.SYNOPSIS...ZONAL FLOW WILL PREVAIL THROUGH THE END OF THE WEEK.
MID UPPER LEVEL RIDGE WILL BUILD ACROSS THE ERN CARIBBEAN EARLY
NEXT WEEK AS MID-UPPER TROF AMPLIFIES ACROSS THE ERN U.S.


&&

.DISCUSSION...ANOTHER CLEAR AND COOL NIGHT ON TAP WITH TEMPS
DROPPING INTO THE MID 50S ACROSS THE CORDILLERA AS WAS THE CASE
EARLY THIS MORNING. A SLIGHT MOISTURE RECOVERY IS EXPECTED
TOMORROW WITH A FEW SHOWERS LIKELY TO DEVELOP WHICH IS A LOT MORE
THAN WE HAVE SEEN SINCE THE START OF THIS WEEK. MOISTURE INCREASES
FURTHER ON SAT AND BECOMES MUCH DEEPER EARLY NEXT WEEK AS WINDS
TURN SOUTHEASTERLY IN RESPONSE TO RETREATING ATLC SFC HIGH AND
MID-UPPER TROF AMPLIFLYING ACROSS THE ERN USA. A SHEARLINE
CONVERGENCE LINE WILL ESTABLISH ACROSS THE DOMINICAN REPUBLIC AND
JUST OUTSIDE OUR MAOR AND HELP MAINTAIN AN UNSETTLED WX PATTERN.
UNDER A SOUTH SOUTHWEST FLOW EXPECT AREAS NORTH OF THE CORDILLERA
TO RECEIVE MOST OF THE RAINFALL.

&&

.AVIATION...VFR CONDITIONS NEXT 24 HRS WITH INCREASING CHANCES OF
SHOWERS AND THUNDERSTORMS LATE SAT AND INTO NEXT WEEK.


&&

.MARINE...NORTHEAST SWELLS AROUND 5 FEET WILL SLOWLY SUBSIDE OVER
THE NEXT DAY OR SO WITH SEAS DROPPING TO 3 FT OR LESS BY MON. SCT
SHOWERS AND THUNDERSTORMS WILL BECOME THE MAIN HAZARD NEXT WEEK.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 70 85 74 84 / 0 10 20 20
STT 74 76 76 77 / 0 10 20 20

Good evening. It looks like starting on Saturday and continuing thru mid next week,moisture increses bigtime in Puerto Rico and adjacent islands. Let's see what occurs with any flooding that may occur in that period.

Good morning. Moisture increases from today and going into most of next week.


AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SAN JUAN PR
1054 AM AST SAT APR 21 2012

.SYNOPSIS...RIDGE OF HIGH PRES EXPECTED TO DEVELOP BY TOMORROW AND
STRENGTHEN THROUGH MID NEXT WEEK AS DEEP CUTOFF LOW FORMS ACROSS
THE OH VALLEY. A LONG FETCH SOUTHEAST FLOW WILL DEVELOP ACROSS THE
AREA BRINGING HOT AND HUMID WEATHER.

&&

.DISCUSSION...IMPRESSIVE CLOSED UPPER LOW EMBEDDED IN THE SRN
STREAM OVR THE GMEX CONTINUES TO DIG PER WATER VAPOR IMAGERY. THIS
FEATURE IS MUCH DEEPER THAN INITIALIZED BY GLOBAL MODELS BASED ON
12Z RAOBS ACROSS THE GULF COAST STATES AND WATER VAPOR IMAGERY.
THIS FEATURE IS EXPECTED TO PHASE WITH SHORTWAVE ENERGY DIGGING
ACROSS THE UPPER MIDWEST TOMORROW AFTERNOON WITH STRONG SFC
CYCLOGENESIS FCST TO TAKE PLACE OFF THE SOUTHEAST U.S. COAST.
GIVEN THAT CLOSED LOW CONTINUES TO DIG ACROSS THE GMEX EXPECT A
SLOWER EVOLUTION OF UPPER LEVEL RIDGE DOWNSTREAM ACROSS OUR AREA
TOMORROW AND MONDAY.

CLOSER TO HOME...SUBSIDENCE CAP THAT WAS IN PLACE ALL WEEK HAS
ERODED BUT MOISTURE REMAINS SOMEWHAT LIMITED FOR LATE APRIL WITH
PW VALUES AROUND 1.5 INCHES. MAIN ELEMENT THAT CALLS MY ATTENTION
THIS MORNING IS DECENT SRH VALUES AROUND 55 M^2/S^2 WITH VALUES
FCST TO PEAK BETWEEN 100-150 M^2/S^2 LATER TODAY ACCORDING TO 12Z
NAM AND 06Z GFS. SO POTENTIAL EXISTS FOR ROTATING UPDRAFTS WITH
ISOLD BRIEF TORNADOES OR WATERSPOUTS WITH ANY STORMS THAT
DEVELOP. STORM MOTION IS FCST TO BE FROM THE WEST SOUTHWEST
BETWEEN 5-10 KTS BASED ON 0-6KM MEAN WINDS.

A HEAT WAVE APPEARS ON TAP FOR EARLY NEXT WEEK UNDER AMPLIFLYING
UPPER RIDGE AND SOUTHEAST FLOW. TEMPS WILL BE ALMOST 10 DEGS
WARMER THAN EARLIER IN THE WEEK WITH OPPRESSIVE HUMIDITY VALUES.
THIS WILL BE QUITE A DRASTIC CHANGE AND DIFFICULT FOR PEOPLE TO
ACCLIMATE GIVEN THAT IS SO EARLY IN THE YEAR AND REFRESHINGLY COOL
AND DRY CONDITIONS THAT WE JUST EXPERIENCED.

&&

.AVIATION...SCT-NMRS TSTMS DEVELOPING ACROSS THE CNTRL MOUNTAIN
RANGE AFTER 16Z POSSIBLY AFFECTING JMZ/JBQ AND JSJ. HAVE VCTS FOR
JSJ AND JBQ AND TEMPO FOR JMZ WITH MVFR CIGS RESTRICTIONS.


&&

.MARINE...SEAS WILL REMAIN BETWEEN 2-4 FT MOST OF THE WEEK IN SE
WIND WAVES. SCT AFTERNOON TSTMS MOVING OFF THE NORTH COAST WILL
THE MAIN THREAT.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 84 75 86 75 / 20 20 40 40
STT 78 75 78 76 / 10 30 30 50

Good morning on this Sunday. The rains have arrived here and flood advisories has popped already.

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
1015 AM AST SUN APR 22 2012

PRC029-031-087-103-119-127-139-221715-
/O.NEW.TJSJ.FA.Y.0134.120422T1415Z-120422T1715Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000 Z.OO/
CANOVANAS PR-NAGUABO PR-SAN JUAN PR-TRUJILLO ALTO PR-CAROLINA PR-
RIO GRANDE PR-LOIZA PR-
1015 AM AST SUN APR 22 2012

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
CANOVANAS...NAGUABO...SAN JUAN...TRUJILLO ALTO...CAROLINA...RIO
GRANDE AND LOIZA

* UNTIL 115 PM AST

* AT 1012 AM AST...DOPPLER RADAR INDICATED MODERATE TO OCCASIONAL
SHOWERS AND ISOLATED THUNDERSTORMS FROM SAN JUAN EAST TO NAGUABO
MOVING TO THE NORTH AROUND 10 MPH. THESE SHOWERS ARE PRODUCING
RAINFALL RATES OF ONE TO TWO INCHES PER HOUR AND ARE CAPABLE OF
PRODUCING STREET FLOODING AND FLOODING IN POOR DRAINAGE AREAS. IN
ADDITION...QUEBRADA GUABA IN NAGUABO HAS EXPERIENCED SIGNIFICANT
RISES AND IS POSSIBLE THIS STREAM COULD GO OUT OF ITS BANKS.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1845 6603 1846 6590 1842 6577 1839 6575
1827 6576 1825 6569 1821 6566 1817 6569
1819 6572 1817 6572 1818 6576 1811 6577
1819 6576 1821 6583 1827 6582 1825 6588
1831 6598 1830 6608 1844 6610 1847 6613

$$

ROSA
------------------------------------------------- -------------------------------

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
954 AM AST SUN APR 22 2012

PRC063-077-085-221645-
/O.NEW.TJSJ.FA.Y.0133.120422T1354Z-120422T1645Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000 Z.OO/
GURABO PR-JUNCOS PR-LAS PIEDRAS PR-
954 AM AST SUN APR 22 2012

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
GURABO...JUNCOS AND LAS PIEDRAS

* UNTIL 1245 PM AST

* AT 951 AM AST...DOPPLER RADAR INDICATED MODERATE TO OCCASIONALLY
HEAVY RAIN IN THE GURABO AND VALENCIANO RIVER BASINS IN
JUNCOS...GURABO AND LAS PIEDRAS. RAIN GAGES HAVE MEASURED RAINFALL
RATES OF 2 INCHES PER HOUR WITH THESE RAINS. THESE COULD LEAD TO
FLOODING OF SMALL STREAMS...URBAN AND POOR DRAINAGE AREAS. SHARP
RISES WITHIN BANKFULL CAN ALSO BE EXPECTED ON THE GURABO AND
VALENCIANO RIVERS.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1825 6588 1825 6585 1828 6584 1826 6582
1817 6583 1817 6586 1812 6588 1813 6592
1823 6595 1821 6600 1822 6601 1827 6601
1830 6603 1831 6603 1831 6597

$$

ROSA

FLOOD ADVISORY
NATIONAL WEATHER SERVICE SAN JUAN PR
1230 PM AST SUN APR 22 2012

PRC027-071-115-221930-
/O.NEW.TJSJ.FA.Y.0135.120422T1630Z-120422T1930Z/
/00000.N.ER.000000T0000Z.000000T0000Z.000000T0000 Z.OO/
ISABELA PR-CAMUY PR-QUEBRADILLAS PR-
1230 PM AST SUN APR 22 2012

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED AN

* URBAN AND SMALL STREAM FLOOD ADVISORY
FOR THE FOLLOWING MUNICIPALITIES...

IN PUERTO RICO
ISABELA...CAMUY AND QUEBRADILLAS

* UNTIL 330 PM AST

* AT 1228 PM AST...DOPPLER RADAR INDICATED SHOWERS AND THUNDERSTORMS
SOME WITH VERY HEAVY RAIN OVER NORTHWEST PUERTO RICO MOVING TO THE
NORTH AROUND 5 MPH. RAINFALL RATES OF ONE TO TWO INCHES PER HOUR
CAN BE EXPECTED WITH THESE THUNDERSTORMS WHICH COULD PRODUCE
FLOODING IN URBAN AND POOR DRAINAGE AREAS.

MOST FLOOD DEATHS OCCUR IN AUTOMOBILES. NEVER DRIVE YOUR VEHICLE INTO
AREAS WHERE THE WATER COVERS THE ROADWAY. FLOOD WATERS ARE USUALLY
DEEPER THAN THEY APPEAR. JUST ONE FOOT OF FLOWING WATER IS POWERFUL
ENOUGH TO SWEEP VEHICLES OFF THE ROAD. WHEN ENCOUNTERING FLOODED
ROADS MAKE THE SMART CHOICE...TURN AROUND...DONT DROWN.

&&

LAT...LON 1850 6698 1851 6697 1849 6691 1850 6684
1839 6681 1835 6682 1837 6691 1839 6692
1838 6695 1839 6703 1848 6706 1852 6710
1852 6704

$$

ROSA

Good afternoon. The next few days will be the same as Sunday with afternoon showers,and warm temperatures.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
207 PM AST SUN APR 22 2012

.SYNOPSIS...MID-UPPER LEVEL RIDGE WILL BUILD OVER THE AREA TONIGHT
AND HOLD THROUGH MID WEEK THEN FLATTEN EARLY NEXT WEEK. SOUTHEAST
FLOW WILL PREVAIL THROUGH MUCH OF THE WEEK WITH TRADE WINDS
RETURNING TO THE AREA AT THE END OF THE WORK WEEK.

&&

.DISCUSSION...SHOWERS AND THUNDERSTORMS START TO DEVELOPED LATE
IN THE MORNING HOURS...AS A MOIST SOUTHEAST WIND FLOW COMBINED
WITH DAYTIME HEATING. RAINFALL ACCUMULATION WERE NEAR 3 INCHES
NEAR GURABO...WHICH PRODUCED RISES IN RIO GURABO EARLY IN THE
AFTERNOON. ANOTHER LINE OF SHOWERS WITH THUNDERSTORMS DEVELOPED
ACROSS THE CORDILLERA CENTRAL...BUT DID NOT LAST FOR MORE THAN ONE
HOUR. CLOUD COVERAGE HAS LIMITED THE DEVELOPMENT OF MORE ACTIVITY
ACROSS PUERTO RICO...BUT CANT BE RULE OUT...AS LATEST SATELITE
IMAGES INDICATED A CLEARING TREND. MOISTURE ACROSS THE AREA IS
EXPECTED TO LINGER THROUGH MID WEEK...WHICH WILL CONTRIBUTE TO THE
DEVELOPMENT OF AFTERNOON SHOWERS WITH THUNDERSTORMS EACH DAY.
ALSO...AS SOUTHEAST TO SOUTH WIND DOMINATES THE REGION...HIGHER
THAN NORMAL MAXIMUM TEMPERATURES WILL BE EXPECTED OVER THE
NORTHERN HALF OF PUERTO RICO. FOR THURSDAY...A MORE EASTERLY TRADE
WIND FLOW WILL RETURN TO THE AREA...WITH MOISTURE DECREASING AS WELL.

&&

.AVIATION...MVFR CONDITIONS WILL CONTINUE OVER TJBQ THROUGH AT
LEAST 22/22Z. ELSEWHERE...VFR CONDITIONS EXPECTED.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 77 87 77 87 / 30 50 30 50
STT 76 86 76 86 / 40 40 40 40

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE SAN JUAN PR
549 AM AST MON APR 23 2012

.SYNOPSIS...AT UPPER LEVELS...HIGH PRESSURE OVER PUERTO RICO WILL MOVE
SLOWLY EAST...CROSSING THROUGH THE U.S. VIRGIN ISLANDS TONIGHT AND
THE WINDWARD ISLANDS TUESDAY NIGHT. WEST SOUTHWEST FLOW WILL
CONTINUE OVER THE AREA UNTIL THE WEEKEND AND SHIFT TO NORTHWEST
EARLY NEXT WEEK AS A RIDGE MOVES INTO THE WESTERN CARIBBEAN. BEST
DIVERGENCE ALOFT WILL BE MID WEEK THIS WEEK.

AT MID LEVELS...AT MID LEVELS...HIGH PRESSURE IN THE SOUTH
CARIBBEAN SEA WILL MOVE INTO THE EASTERN CARIBBEAN ON TUESDAY AS
STRONG TROUGHING DOMINATES THE WESTERN CARIBBEAN. HIGH PRESSURE
GRADUALLY RETURNS TO THE ENTIRE CARIBBEAN AFTER THE WEEKEND.

AT LOWER LEVELS...STRONG LOW PRESSURE HAS ENTERED NEW JERSEY AND
WILL CONTINUE TO THE NORTH. THE ASSOCIATED TROUGH WILL MOVE SLOWLY
EAST THROUGH THE WESTERN CARIBBEAN TODAY AND KEEP MOIST SOUTH TO
SOUTHEASTERLY FLOW OVER THE LOCAL AREA UNTIL ABOUT MIDDAY ON
WEDNESDAY. HIGH PRESSURE EAST OF FLORIDA WILL JOIN WITH THE HIGH
IN THE NORTH CENTRAL ATLANTIC TO KEEP EASTERLY TRADE WIND FLOW
THROUGH EARLY NEXT WEEK. VERY GOOD MOISTURE WILL CONTINUE THROUGH
THE WORK WEEK BUT WILL DROP OFF DRAMATICALLY OVER THE WEEKEND.
MOISTURE IS EXPECTED TO RECOVER EARLY NEXT WEEK AS EASTERLY FLOW
CONTINUES.

&&

.DISCUSSION...SOUTHEAST FLOW WAS EVIDENT OVER THE AREA AS EVEN
LAND BREEZES ON THE SOUTH COAST GAVE WAY TO INCOMING SHOWERS.
SHOWERS WITH LIGHT AMOUNTS WERE SEEN MOST OF THE NIGHT BEGINNING
ON THE EAST COAST AND SPREADING ALONG THE SOUTH COAST. THIS IS A
GOOD INDICATOR THAT SCATTERED SHOWERS WILL CONTINUE OVER THE
SOUTH AND EAST EXTREMITIES OF PUERTO RICO AND ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS WITH SIGNIFICANT AMOUNTS OF RAIN IS IN
STORE FOR THE NORTHWESTERN AND NORTH CENTRAL COASTS AND INTERIOR
PORTIONS OF THE ISLAND. SCATTERED SHOWERS WILL ALSO CONTINUE
AROUND...AND SOMETIMES OVER...THE U.S. VIRGIN ISLANDS. THIS TREND
WILL CONTINUE INTO WEDNESDAY. MODELS ARE NOT SHOWING AS MUCH
MOISTURE AS ONE WOULD EXPECT FROM THE TWO PLUS INCHES OF
PRECIPITABLE WATER IN THE 23/00Z SOUNDING...HOWEVER THE WATER
VAPOR IMAGERY DOES SHOW A WIDE SWATH OF BETTER MOISTURE THAT
MOVED OVER THE AREA OVERNIGHT LAST NIGHT ALSO BEGINNING AROUND
23/00Z AND WOULD EXPECT THAT THIS WILL CONTINUE TO KEEP SHOWER
ACTIVITY LEVELS HIGH. ALSO BUMPED UP MOS TEMPERATURES ON THE
NORTH COAST ANOTHER 2 DEGREES. WARM AIR HAS CONTINUED TO FLOW
FROM THE SOUTHEAST AND MOS WAS SEVERAL DEGREES TOO COOL ON THE
NORTH COAST YESTERDAY. MANY AREAS ON THE NORTH COAST WILL SEE
LOWER 90S BY MIDDAY. ALL THE MODELS SHOWED TODAY AS HAVING THE
HIGHEST 1000-850 MB THICKNESS VALUES OF ANYTIME THIS WEEK. WITH
THIS GOOD MOISTURE WE LOOK FOR AFTERNOON URBAN AND SMALL STREAM
FLOODING TO RECUR ESPECIALLY IN THE NORTH CENTRAL PORTIONS OF
PUERTO RICO...BUT COULD OCCUR ANYWHERE IN THE NORTH HALF OF THE
ISLAND TODAY THROUGH WEDNESDAY. SHOWERS FROM THE HEATING AND
BETTER MOISTURE AT UPPER LEVELS WILL BE AIDED BY INCREASED
DIVERGENCE ALOFT TUESDAY AND WEDNESDAY. THEREFORE ALTHOUGH THE
BEST MOISTURE STILL STAYS OVER HISPANIOLA...EXPECT TO SEE
CONTINUED GOOD COVERAGE OVER MOST OF PUERTO RICO THROUGH
WEDNESDAY. ON THURSDAY...WITH WIND FLOW TURNING TO THE EAST...
THE FOCUS OF THE SHOWERS WILL SHIFT TO THE WEST AND INTERIOR
PORTIONS OF PUERTO RICO AND DIMINISH OVER THE U.S. VIRGIN
ISLANDS. DRIER WEATHER IS EXPECTED OVER THE WEEKEND...BUT MOISTURE
WILL RECOVER LATE SUNDAY OR MONDAY.

&&

.AVIATION...
MAINLY VFR CONDITIONS EXPECTED IN THE MORNING WITH A FEW PASSING
SHOWERS AFFECTING TJPS EARLY. FOR THE AFTERNOON...EXPECT VFR TO
MVFR CONDITIONS AND MOUNTAIN OBSCURATIONS DUE TO DEVELOPING
SHOWERS ACROSS PUERTO RICO. VCTS POSSIBLE AT TJSJ...TJMZ...AND
TJPS. NUMEROUS SHRA/TSRA EXPECTED ACROSS NORTHWESTERN PUERTO
RICO...THEREFORE TEMPO MVFR/IFR CONDITIONS ARE LIKELY IN AND
AROUND TJBQ. EXPECT PREVAILING SOUTHEASTERLY WINDS AT AROUND 10
KNOTS WITH SEA BREEZE VARIATIONS...PARTICULARLY AT TJMZ AND TJBQ.

&&

.MARINE...MARINE CONDITIONS REMAIN GENERALLY 3-5 KNOTS AND 10 TO
17 KNOTS FOR THE NEXT SEVERAL DAYS. HIGHER WINDS MAY BE SEEN LATER
IN THE SOUTHERN PART OF THE CARIBBEAN ZONES AS HIGH PRESSURE
RETURNS TO THE WESTERN ATLANTIC EAST OF FLORIDA.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 90 76 87 75 / 50 30 50 30
STT 84 77 85 77 / 40 50 50 30

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
317 PM AST MON APR 23 2012

.SYNOPSIS...TROUGH OF LOW PRES ACROSS HISPANIOLA WILL HOLD THROUGH
MID WEEK THEN WEAKEN. TRADE WINDS WILL RETURN TO THE AREA THU AS
HIGH PRES BUILDS NORTH OF THE BAHAMAS.

&&

.DISCUSSION...UPPER RIDGE AXIS OVER THE ERN DOM REP AND THE MONA
PASSAGE WILL CONTINUE TO SLIDE EAST AS DEEP CUTOFF LOW OVER THE OH
VALLEY LIFTS NORTHEAST INTO SERN CANADA. 12Z GFS40 VERIFIED QUITE
WELL TODAY SHOWING STRONG SUBSIDENCE AND DOWNWARD MOTION ACROSS
THE ISLAND. TEMPERATURES HAVE SOARED INTO THE 90S AS WAS
ADVERTISED FOR THE PAST SVRL DAYS. RIDGE AXIS WILL SLIDE EAST TO
NEAR 60W BY 00Z WED WITH GFS INDICATING A SLIGHTLY BETTER SFC
CONVERGENCE TOMORROW AND BETTER UPWARD MOTION TUE AND WED.
ANTICIPATE SCT SHOWERS TO RETURN TO NW PR TUE AND WED. THERE IS
ALSO A SLIGHT COOLING AT 950 AND 850 MB WITH SHOULD RESULT IN A
DEG OR TWO OF COOLING AT THE SFC. CONDITIONS LOOK VERY ACTIVE OVER
HISPANIOLA AND EXPECT CONVECTIVE DEBRIS AND POSSIBLE SHOWERS TO
AFFECT THE MONA PASSAGE ESPECIALLY TUE NIGHT INTO WED MORNING.

UPPER TROF ACROSS ERN NOAM LIFTS OUT OVER TOP OF MID ATLC RIDGE
THU WITH UPPER RIDGE RETROGRADING OVER THE AREA OVR THE WEEKEND.
SFC HIGH PRES BUILDS NORTH OF THE BAHAMAS THU WITH PRES GRADIENT
TIGHTENING AND TRADES RETURNING TO THE LOCAL AREA. WINDS STAY UP
OVR THE WEEKEND WITH A SIG DRYING TREND FCST FRI-MON.


&&

.AVIATION...EXPECT PREVAILING VFR CONDITIONS ACROSS THE LOCAL
ISLANDS AND AT ALL TAF SITES THROUGH THE FORECAST PERIOD. HOWEVER...
BRIEF MVFR CONDITIONS AND LOCAL MOUNTAIN OBSCURATIONS POSSIBLE IN
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS TUESDAY AFTERNOON.


&&

.MARINE...SEAS 2-4 FEET THROUGH FRI BUT INCREASE OVER THE WEEKEND
TO 4-6 FT AS TRADE WINDS INCREASE.


&&


.PRELIMINARY POINT TEMPS/POPS...
SJU 78 87 78 85 / 0 50 0 20
STT 79 86 79 79 / 20 20 20 20

It has been hot,hot,hot today in PR.


.CLIMATE...SO FAR HIGH AT SJU AIRPORT HAS BEEN 91F AND RECORD IS
92F. SO THERE STILL A CHANCE OF TYING OR BREAKING THE RECORD
TODAY. RECORD FOR TOMORROW IS 95F AND WILL BE IMPOSSIBLE TO BREAK
ESPECIALLY GIVEN SOME SLIGHT COOLING AT 950 AND 850 MBS.

Plenty of rain is expected in the Haiti/Dominican Republic area in the next two days.

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
225 PM EDT MON APR 23 2012

NOTE: THERE IS A RISK OF HEAVY RAINFALL TO AFFECT DOMINICAN
REPUBLIC AND HAITI DURING THE NEXT FOUR DAYS...WITH STRONGEST
CONVECTION TO AFFECT NORTHERN SECTIONS OF THE ISLAND DURING
TUESDAY AND WEDNESDAY. THIS IS A POTENTIALLY DANGEROUS SITUATION
WITH A RISK FOR FLASH FLOODS AND MUDSLIDES REMAINING THROUGH
THURSDAY.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1004 PM AST MON APR 23 2012

.UPDATE...A GENERALLY DRY AND STABLE AIR MASS IS EXPECTED TO
PREVAIL ACROSS THE LOCAL ISLANDS OVERNIGHT AND EARLY TOMORROW.
LATEST SATELLITE AND RADAR IMAGES THIS EVENING DEPICTED ONLY A FEW
ISOLATED TO SCATTERED SHOWERS MAINLY ACROSS THE CARIBBEAN COASTAL
WATERS. WITH A SOUTH SOUTHEAST LOW LEVEL WIND FLOW...FEW OF THESE
SHOWERS AFFECTED THE SOUTHERN SECTIONS OF PUERTO RICO. IN COMPARISON
WITH PREVIOUS DAYS...A SLIGHT INCREASE IN MOISTURE ARE EXPECTED
TOMORROW WITH SCATTERED SHOWERS AND POSSIBLE A FEW THUNDERSTORMS
ACROSS NORTH AND NORTHWEST PUERTO RICO DURING THE AFTERNOON. THE
SOUTHEAST LOW LEVEL WIND FLOW WILL CONTINUE TO PROMOTE WARMER THAN
NORMAL TEMPERATURES ESPECIALLY ACROSS NORTHERN PUERTO RICO DURING
THE NEXT FEW DAYS.

Good morning. More warm temperatures are expected today in PR with little rain.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
552 AM AST TUE APR 24 2012

.SYNOPSIS...TROUGH OVER HISPANIOLA EXPECTED TO REMAIN UNTIL EARLY
WEDNESDAY. THEREAFTER...SURFACE HIGH PRESSURE WILL BUILD OVER THE
BAHAMAS...MOVING EAST TO THE NORTH OF THE LOCAL AREA...TRADE WINDS
RETURN FOR THURSDAY.

&&

.DISCUSSION...UNDER THIS SOUTHEASTERLY FLOW...ONLY LIGHT ISOLATED
SHOWERS WERE OBSERVED. PRECIPITABLE WATER AT THE 24/00Z SOUNDING
WAS 1.86 INCHES WHILE SATELLITE DERIVED BLENDED TOTAL PRECIPITABLE
WATER AT 24/07Z INDICATED THAT THE PRECIPITABLE WATER HAD GONE DOWN TO
1.65 INCHES. FORECAST SOUNDINGS SUGGEST THAT THE CONDITIONS TODAY
WILL BE SIMILAR TO THE CONDITIONS YESTERDAY...WITH ABOUT 1000 J/KG
LESS CAPE THAN YESTERDAY AND AN INVERSION AT ABOUT 800MB. COMPUTER
MODELS KEEP SUGGESTING THAT THE NORTHWESTERN SECTIONS OF PUERTO
RICO WILL OBSERVE NUMEROUS SHOWERS...HOWEVER...THAT HAS NOT BEEN
THE CASE FOR THE PAST FEW DAYS. THEREFORE...WE WERE CONSERVATIVE
WITH THE POPS GIVEN THE FACT THAT NOT MUCH HAS CHANGED FROM THE
PAST FEW DAYS. TEMPERATURES WILL BE WARM ONCE AGAIN WITH HIGHS
EXPECTED IN THE 90S ACROSS THE LOWER ELEVATIONS OF PUERTO RICO AND
IN THE MID TO UPPER 80S ACROSS THE USVI.


&&

.AVIATION...VFR CONDITIONS WILL CONTINUE TO PREVAIL ACROSS ALL
TAF SITES NEXT 24 HRS WITH EXCEPTIONS OF BRIEF MVFR AT TNCM AND
TKPK. HOWEVER...AFT 24/17Z BRIEF MVFR CONDITIONS AND LOCAL
MOUNTAIN OBSCURATIONS WILL REMAIN POSSIBLE ACROSS THE NORTHWEST
AND NORTH CENTRAL SLOPES OF PUERTO RICO INCLUDING THE VICINITY OF
TJBQ THROUGH ABOUT 24/22Z. LLVL WINDS 12 KT OR LESS FROM SSE AT OR
BELOW 7 KFT. STILL SEEING UP TO 45 KT BTWN 35-45 KFT. A SHEAR LINE
WITH SCT CONVECTION WILL BE ENCOUNTERED ABOUT 150-200 NM NORTHWEST
OF SAN JUAN.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 89 76 88 75 / 20 10 20 10
STT 85 77 85 76 / 10 20 20 10

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
236 PM AST TUE APR 24 2012

.SYNOPSIS...THE UPPER RIDGE OVER THE CARIBBEAN EXTENDS ACROSS PUERTO
RICO AND VIRGIN ISLANDS THEN INTO THE CENTRAL ATLANTIC...WITH LONG
WAVE TROUGH EXTENDING SOUTHWARDS ALONG THE EASTERN SEABOARD OF THE
UNITED STATES INTO THE NORTHWEST CARIBBEAN. THIS IS SUPPORTED BY A
BROAD MID LEVEL TROUGH JUST EAST OF THE REGION. THIS PATTERN WILL
PROVIDE SOME VENTILATION FOR AFTERNOON CONVECTION MAINLY ACROSS THE
NORTHWEST SECTIONS OF PUERTO RICO TODAY. IN ADDITION...A WEAK MID
LEVEL PERTURBATION IS EXPECTED TO ROUND THE BASE OF THE TROUGH
LATE THIS AFTERNOON AS IT SLOWLY LIFTS EAST NORTHEAST AND SLIGHTLY
ERODES THE UPPER RIDGE NOW OVERHEAD. A SURFACE TROUGH EXTENDS
ACROSS THE WEST ATLANTIC SOUTHWARDS ACROSS CUBA THEN INTO THE
NORTHWEST CARIBBEAN. A SECONDARY FRONTAL TROUGH EXTENDS FROM THE
WEST CENTRAL ATLANTIC SOUTHWARDS ACROSS HISPANIOLA THEN INTO THE
CENTRAL CARIBBEAN. THE LATTER MENTIONED TROUGH WILL SLOWLY DRIFT
WESTWARD OVER THEN NEXT DAY OR SO WHILE WEAKENING...AS STRONG
ATLANTIC HIGH WILL REESTABLISH ITSELF NORTH OF THE FORECAST AREA.
THIS WILL EVENTUALLY RESULT IN AN INCREASE THE EASTERLY TRADE WIND
FLOW BY THE LATTER PART OF THE WORK WEEK AND INTO THE UPCOMING
WEEKEND.

&&

.DISCUSSION...PRESENT SYNOPTIC PATTERN ACROSS THE AREA ALONG WITH
LATEST MODEL GUIDANCE...SUGGESTS WEAK SOUTH SOUTHEAST LOW LEVEL WIND
FLOW TO CONTINUE TO DOMINATE THE WEATHER CONDITIONS AT LEAST THROUGH
WEDNESDAY AFTERNOON...BEFORE IT BECOMES MORE EASTERLY BY THURSDAY.
LATEST SATELLITE IMAGERY SHOWED FAIRLY DRY MID TO UPPER LEVEL AIR
MASS...WITH SHALLOW PATCHES OF TROPICAL MOISTURE BEING TRANSPORTED
ACROSS THE REGION IN THE PREVAILING WIND FLOW. PWAT VALUES ACROSS
THE LOCAL AREA AND NORTHEAST CARIBBEAN RANGED BETWEEN 1.70 TO 1.90
INCHES. THEREFORE WITH THIS WEAKER WIND FLOW TODAY... EXPECT MORE
LOCAL TERRAIN AND SEA BREEZE CONVERGENCE TODAY IN SOME AREAS. THIS
WILL LEAD TO SOME AFTERNOON CONVECTION MAINLY ACROSS PUERTO RICO.
INTENSE HEATING AND PROXIMITY OF A MID LEVEL PERTURBATION MAY
LEAD TO AN ISOLATED THUNDERSTORM DEVELOPMENT WHICH WILL BE CAPABLE
OF PRODUCING LOCALLY HEAVY RAINFALL IN ISOLATED SPOTS ACROSS THE
NORTHWEST SECTIONS OF PUERTO RICO. HOWEVER... EXPECT THIS ACTIVITY
TO BE SHORT LIVED AND NOT WIDESPREAD. MOST OF AFTERNOON CONVECTION
WILL QUICKLY DIMINISHING AFTER SUNSET. SIMILAR CONDITIONS ARE
EXPECTED FOR THE REST OF THE WEEK AND INTO THE WEEKEND WITH LIMITED
MOISTURE ADVECTION...AND MAINLY LOCALLY AND AND DIURNALLY INDUCED
AFTERNOON CONVECTION. THE MAIN DIFFERENCE OVER THE NEXT FEW DAYS
WILL BE A CHANGE IN THE STEERING FLOW AS THE TRADE WINDS INCREASE
AND BECOME MORE EASTERLY BY THE END OF THE WEEK AS THE LOCAL
SURFACE PRESSURE GRADIENT TIGHTENS.

&&

.AVIATION...EXPECT PREVAILING VFR CONDITIONS ACROSS THE LOCAL
ISLANDS AND MOST THE TAF SITES THROUGH THE FORECAST PERIOD. BRIEF
MVFR CONDITIONS AND LOCAL MOUNTAIN OBSCURATIONS ARE STILL POSSIBLE
IN SCT SHOWERS...MAINLY IN AND AROUND TJBQ. LLVL SOUTHEASTERLY WINDS
WILL CONTINUE THROUGH WEDNESDAY NIGHT...SHIFTING TO THE EAST ON
THURSDAY MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 87 74 85 / 10 20 10 10
STT 77 85 76 86 / 20 20 10 10

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
257 PM AST WED APR 25 2012

.SYNOPSIS...STATIONARY FRONT OVER THE HISPANOLA WILL DISSIPATE ON
THURSDAY AS LOSES THE UPPER LEVEL SUPPORT. AN INDUCED/PREFRONTAL
TROUGH WEST OF THE FORECAST AREA IS EXPECTED TO WEAKEN THROUGH
FRIDAY AS MOVES WEST INTO THE CENTRAL/WESTERN CARIBBEAN. A HIGH
BUILDING OVER THE NORTH CENTRAL ATLANTIC WILL BRING A RETURN OF
MODERATE TO LOCALLY FRESH EASTERLY TRADE WINDS ON THURSDAY. UPPER
LEVEL RIDGE ACROSS THE LESSER ANTILLES WILL REESTABLISH ITSELF
OVER PUERTO RICO DURING THE WEEKEND...RESULTING IN MUCH LESS
SHOWER ACTIVITY.

&&

.DISCUSSION...IR SATELLITE IMAGERY REVEALS AREAS OF STRONG CONVECTION
ASSOCIATED WITH THE STATIONARY FRONT AND THE INDUCED TROUGH OVER
THE HISPANOLA AND PORTIONS OF THE MONA PASSAGE. SATELLITE DERIVED
PW DEPICTS AN ELONGATED BAND OF DEEP MOISTURE WITH PRECIPITABLE
WATER VALUES ABOVE 2.25 INCHES JUST NORTHWEST OF THE FORECAST AREA.
THE PROXIMITY OF THESE FEATURES AND ITS ASSOCIATED MOISTURE...ALONG
WITH THE FAVORABLE UPPER LEVEL DYNAMICS IS RESULTING IN ORGANIZED
CONVECTION ACROSS THE FORECAST AREA. ATTM...THE MOST ACTIVE CONVECTION
IS OCCURRING ACROSS THE LOCAL ATLANTIC WATERS AND NORTHERN HALF OF
PUERTO RICO. WEATHER CONDITIONS WILL GRADUALLY IMPROVE DURING THE
NEXT FEW DAYS AS THE TROUGH MOVES WESTWARD INTO THE CENTRAL/WESTERN
CARIBBEAN. FOR THE UPCOMING WEEKEND...UPPER LEVEL RIDGE REBUILDS
ACROSS THE LOCAL REGION...RESULTING IN THE RETURN OF A MORE STABLE
AIR MASS OVER THE ISLANDS.

&&

.AVIATION...EXPECT AFTN SHRA AND ISOLD TSRA ACROSS THE INTERIOR
SECTIONS OF PR TO DIMINISH BY SUNSET LEAVING MAINLY VFR CONDS ACROSS
PR AND REST OF THE LOCAL ISLANDS THROUGH THE FCST PRD. VFR CONDS
WILL CONTINUE AT ALL TAF SITES NXT 24 HRS...EXCEPT FOR BRIEF
MVFR/IFR CONDITIONS IN EMBEDDED TSTMS ACROSS THE LOCAL ATLANTIC EN
ROUTE TO TJSJ AND TJBQ FM THE U.S. MAINLAND. LCL MTN TOP OBSCR WILL
ALSO REMAIN PSBL ACROSS THE CORDILLERA CENTRAL OF PR IN SHRA/ISOLD TSRA
TIL 25/23Z.

&&

.MARINE...A MODERATE NORTHWEST SWELLS WILL CONTINUE TO AFFECT THE
LOCAL ATLANTIC WATERS AND CARIBBEAN PASSAGES THROUGH THURSDAY. SEAS
WILL RANGE BETWEEN 3 TO 5 FEET ACROSS THE WATERS THROUGH EARLY
FRIDAY. WINDS WILL BACK TO THE EAST LATE TONIGHT THROUGH THURSDAY
MORNING.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 85 75 84 / 20 20 40 40
STT 77 86 76 86 / 20 20 50 50

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
949 PM AST WED APR 25 2012

.UPDATE...LATEST SATELLITE AND RADAR IMAGES THIS EVENING
DEPICTED A LARGE AREA OF SHOWERS AND THUNDERSTORMS EXTENDING FROM
THE MONA CHANNEL NORTHEASTWARD ACROSS NORTHWEST PUERTO RICO AND INTO
THE ATLANTIC COASTAL WATERS. THIS ACTIVITY WAS ASSOCIATED WITH A
FRONTAL TROUGH EXTENDING FROM THE CENTRAL CARIBBEAN...NORTHEASTWARD
ACROSS HISPANIOLA AND THEN INTO THE CENTRAL ATLANTIC. THIS TROUGH
WILL SLOWLY DRIFT WESTWARD OVER THEN NEXT FEW DAYS WHILE
WEAKENING...AS THE ATLANTIC HIGH BUILD NORTH OF THE FORECAST AREA.
THIS WILL EVENTUALLY RESULT IN AN INCREASE IN THE EASTERLY TRADE
WIND FLOW BY TOMORROW AND INTO THE UPCOMING WEEKEND. AN UPPER
LEVEL RIDGE WILL DEVELOP ACROSS THE REGION DURING THE UPCOMING
WEEKEND AND EARLY NEXT WEEK...BRINGING A MORE STABLE AND DRY AIR
MASS ACROSS THE LOCAL ISLANDS...WITH A RETURN TO THE TYPICAL
DIURNAL AND NOCTURNAL INDUCED SHOWER ACTIVITY.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
541 AM AST THU APR 26 2012

.SYNOPSIS...SURFACE HIGH PRESSURE ACROSS THE CENTRAL ATLANTIC WILL
DOMINATE THE LOCAL AREA DURING THE NEXT FEW DAYS. PATCHES OF LOW
LEVEL MOISTURE IN THE TRADE WINDS...WILL AFFECT THE LOCAL REGION
FROM TIME TO TIME.

&&

.DISCUSSION...ONLY LIGHT PASSING SHOWERS HAVE BEEN AFFECTING THE
REGION DURING THE EARLY MORNING HOURS. SURFACE HIGH PRESSURE
SYSTEM LOCATED ACROSS THE CENTRAL ATLANTIC WILL MAINTAIN RELATIVE
STABLE ATMOSPHERIC CONDITIONS OVER THE AREA THROUGH AT LEAST
SUNDAY. PATCHES OF LOW LEVEL MOISTURE IN THE TRADE WIND FLOW WILL
AFFECT THE REGION FROM TIME TO TIME DURING THE NEXT FEW DAYS. IN
FACT...ALL COMPUTER MODEL AGREED ON BRINGING TO THE AREA ONE OF
THIS PATCHES BY FRIDAY MORNING. HOWEVER...NO SIGNIFICANT RAINFALL
ACCUMULATION IS EXPECTED...SINCE WINDS ARE INCREASING AND ARE GOING
TO MOVE THESE PATCHES QUICKLY OVER THE AREA. IN THE
MEANTIME...EXPECT THE DEVELOPMENT OF SHOWERS WITH ISOLATED
THUNDERSTORMS EVERY AFTERNOON...MAINLY OVER THE WESTERN INTERIOR
AND WEST SECTIONS OF PUERTO RICO...AND POSSIBLE OVER THE WESTERN
PART OF THE U.S. VIRGIN ISLANDS. IN THE LONG TERM...AT THIS
MOMENT...NO SIGNIFICANT WEATHER EVENTS ARE FORECAST TO AFFECT THE
LOCAL ISLANDS.

&&

.AVIATION...EXPECT AFTN SHRA AND ISOLD TSRA ACROSS THE WESTERN
INTERIOR SECTIONS OF PR AFTER 17Z. VFR CONDS WILL CONTINUE AT ALL
TAF SITES NXT 24 HRS...EXCEPT FOR BRIEF MVFR/IFR CONDITIONS IN
EMBEDDED TSTMS OVER THE TERMINAL OF JMZ THIS AFTERNOON. PREVAILING
WIND WILL BE FROM THE EAST FROM 10 TO 15 MPH WITH HIGHER GUSTS ALONG
THE COASTAL AREAS.



&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 85 75 85 75 / 20 40 40 20
STT 84 75 86 76 / 20 50 50 20

Good afternoon. Here is the Caribbean discussion by HPC:

TROPICAL DISCUSSION - INTERNATIONAL DESKS
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
119 PM EDT THU APR 26 2012

DISCUSSION FROM APR 26/00 UTC: ON WESTERN PORTIONS OF THE
DOMAIN...A LONG WAVE RIDGE EXTENDS NORTH ACROSS MEXICO TO THE
WESTERN USA ALONG 103W. THE STRONG MID/UPPER LEVEL RIDGE PATTERN
WILL HOLD DURING THE NEXT 24-36 HRS...THEN QUICKLY FLATTENS OVER
THE USA/NORTHWESTERN STATES OF MEXICO BY 48-60 HRS AS A TROUGH
LIFTS OVER THIS AXIS. THE STRONG RIDGE PATTERN IS TO MEANWHILE
FAVOR A MID/LOW LEVEL CONVERGENT-SUBSIDENT PATTERN ACROSS MEXICO
AND THE GULF. THIS TENDS TO WEAKEN THROUGH 66-72 HRS...TO ALLOW
LATE AFTERNOON CONVECTION TO DEVELOP ALONG THE SIERRA MADRE
ORIENTAL OF MEXICO.

AS EVIDENT ON THE WATER VAPOR IMAGERY ANIMATION...THE
SUBEQUATORIAL RIDGE HAS BEGUN ITS NORTHWARD/WESTWARD EXPANSION
ACROSS THE EASTERN CARIBBEAN AND INTO THE NORTH ATLANTIC. THIS IS
STRENGTHENING THE TRADE WIND CAP...WITH SATELLITE DERIVED PWAT
ANALYSIS SHOWING EROSION OF AVAILABLE MOISTURE ACROSS THE LESSER
ANTILLES. UPPER LEVEL RIDGE REACHES MAXIMUM AMPLITUDE LATER THIS
EVENING...AS IT IS TO EXTEND BETWEEN 75W-55W NORTHWARD TO 30N. THE
BROAD/STRONG RIDGE PATTERN IS TO HOLD THROUGH SUNDAY MORNING.
INITIALLY...A CAP WILL ESTABLISH AROUND 700 HPA. BUT...BY FRIDAY
EVENING/EARLY SATURDAY MORNING...IT WILL DROP TO 800/850 HPA. AS
THE CAP STRENGTHENS...IT WILL SUSTAIN GRADUAL EROSION OF AVAILABLE
MOISTURE ACROSS THE EASTERN CARIBBEAN ISLANDS...WITH GLOBAL
GUIDANCE AGREEING ON PWAT MINIMA ON SATURDAY. BUT THROUGH SUNDAY
MORNING THE CAP STARTS TO SLACKEN...AND MOISTURE IT TO THEN SLOWLY
SURGE EAST ACROSS THE ISLANDS.

AT LOW LEVELS...POLAR FRONT MEANDERING OVER THE BAHAMAS WILL
DISSIPATE DURING THE DAY...WHILE SIMULTANEOUSLY A HIGH PRESSURE
RIDGE ESTABLISHES OVER THE WESTERN ATLANTIC/NORTH OF THE ISLANDS.
THIS WILL TIGHTEN PRESSURE GRADIENT WHILE ALSO FAVORING A BRISK
EASTERLY FLOW ACROSS THE NORTHEAST CARIBBEAN ISLANDS. THE BOUNDARY
LAYER WINDS ARE TO PEAK AT 15-20KT OVER THE NORTHERN CARIBBEAN AND
20-25KT OVER THE SOUTHERN CARIBBEAN. THE BRISK EASTERLIES ARE TO
TRIGGER STREAMERS ACROSS THE NORTHERN LEEWARD/VIRGIN ISLES THAT
ARE TO AFFECT EASTERN PORTIONS OF PUERTO RICO DURING THE MORNING
HOURS. THESE ARE TO ALSO FAVOR LATE MORNING/AFTERNOON CONVECTION
ON THE WESTERN INTERIOR PORTIONS OF PUERTO RICO...WITH MOST ACTIVE
TODAY WHEN WE EXPECT MAXIMA OF 20-30MM. BUT AS THE SUBSIDENCE CAP
STRENGTHENS...EXPECTING A DECREASE IN ACTIVITY THROUGH FRIDAY
AFTERNOON/SATURDAY. THIS IS TO ALSO HAVE AN IMPACT ON WEATHER
CONDITIONS ACROSS CENTRAL PORTIONS OF HISPANIOLA...WHERE WE EXPECT
RAINFALL AMOUNTS OF 05-10MM/DAY AND MAXIMA OF 15-25MM/DAY THROUGH
36-48 HRS. BY 72-84 HRS THIS WILL DECREASE TO 00-05MM/DAY AND
MAXIMA OF 10MM.

A MID/UPPER LEVEL TROUGH SEPARATES THE SUBTROPICAL RIDGE ON
WESTERN PORTIONS OF THE DOMAIN FROM THE SUBEQUATORIAL RIDGE TO THE
EAST. THE TROUGH EXTENDS TO THE SOUTH-SOUTHWEST ACROSS FLORIDA
PENINSULA/CUBA-GUATEMALA/HONDURAS TO THE EASTERN PACIFIC. THROUGH
36-48 HRS THE TROUGH WILL CUT OFF...WITH A CLOSED LOW TO FORM OVER
THE NORTHWEST CARIBBEAN. THROUGH 60-72 HRS THE LOW WILL LIFT NORTH
ACROSS WESTERN CUBA TO THE BAHAMAS. ALSO AT UPPER LEVELS...A
SUBTROPICAL JET MAXIMA BOUNDS THE FRINGES OF THIS
TROUGH...ROUNDING BASE OF THE TROUGH AND LIFTING NORTH ACROSS THE
WESTERN CARIBBEAN TO CUBA EARLY IN THE CYCLE. THROUGH 60-72 HRS
THE JET MAXIMA IS TO WEAKEN AS IT LIFT ACROSS CUBA TO THE BAHAMAS.
EARLY IN THE CYCLE...AS THE JET ORIGINATES OVER HONDURAS...IT IS
TO FAVOR A DIVERGENT PATTERN ALOFT ACROSS NORTHEAST
HONDURAS/NICARAGUA-CENTRAL CARIBBEAN...SHIFTING NORTH AS THE JET
RELOCATES.

THE TROUGH ALOFT IS INTERACTING WITH AN INVERTED LOW LEVEL TROUGH
OVER THE CENTRAL CARIBBEAN. THIS FAVORS A SURGE IN CONVECTIVE
ACTIVITY THAT IS SPREADING NORTH TOWARDS JAMAICA AND NORTHWEST
TOWARDS THE CAYMAN ISLANDS. ACROSS JAMAICA IT IS TO FAVOR RAINFALL
AMOUNTS OF 15-20MM/DAY AND MAXIMA OF 25-50MM/DAY...WHILE OVER THE
CAYMAN ISLANDS EXPECTING ACCUMULATION OF 10-15MM/DAY AND MAXIMA OF
20-45MM/DAY. MOISTURE IS TO ALSO SPREAD WEST ACROSS ISLA DE LA
PROVIDENCIA AND SAN ANDRES...TO SUSTAIN RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM/DAY. OVER NORTHEASTERN NICARAGUA
AND HONDURAS EXPECTING RAINFALL AMOUNTS OF 15-20MM/DAY AND MAXIMA
OF 25-50MM/DAY BY 60-84 HRS. UNDER INFLUENCE OF THE MID/UPPER
TROUGH... MOISTURE WILL THEN LIFT NORTH ACROSS CUBA INTO THE
BAHAMAS...WHERE ACTIVITY IS TO CONVERGE ALONG AN INVERTED
TROUGH/ILL ORGANIZED CYCLONIC CIRCULATION. ACROSS CUBA EXPECT
ACCUMULATION OF 15-20MM/DAY AND MAXIMA OF 35-70MM/DAY BY 36-60
HRS...WITH LOCALIZE MAXIMA IN EXCESS OF 100MM ACROSS ISLA DE LA
JUVENTUD. ACROSS THE BAHAMAS EXPECTING RAINFALL ACCUMULATION OF
15-20MM/DAY AND MAXIMA OF 30-60MM/DAY BY 48-72 HRS. NOTE THAT FOR
THIS AREA THE GLOBAL ENSEMBLE MEMBERS ARE SHOWING MAXIMA OF NEARLY
100MM FOR DAYS 03-04.

THE DEEP TROUGH OVER CENTRAL AMERICA/EASTERN PACIFIC IS
INTERACTING WITH THE EASTERN PACIFIC ITCZ...STRENGTHENING LOW
LEVEL CYCLONIC CIRCULATION/TROUGH PATTERN WHILE DRAWING THE
CONVERGENCE ZONE NORTH TOWARDS PANAMA-COSTA RICA. THE CONVERGENCE
ZONE IS TO ENTER THE AZUERO PENINSULA IN PANAMA BY 48-54
HRS...WHERE IT IS TO THEN MEANDER THROUGH AT LEAST 96-108 HRS.
THIS...IN-TURN...WILL FAVOR A GRADUAL INCREASE IN CONVECTION
ACROSS THE ISTHMUS. INITIALLY EXPECTING RAINFALL AMOUNTS OF
05-10MM/DAY AND MAXIMA OF 15-25MM/DAY. THIS IS TO INCREASE TO
15-20MM/DAY AND MAXIMA OF 25-50MM/DAY BY 48-84 HRS. ON THE CAUCA
VALLEY IN SOUTHWEST COLOMBIA...EXPECTING RAINFALL AMOUNTS OF
10-15MM/DAY AND MAXIMA OF 20-35MM/DAY. OVER NORTHWEST COLOMBIA/EJE
CAFETERO TO THE DARIEN IN PANAMA...10-15MM/DAY EXPECTING
ACCUMULATION OF 15-20MM/DAY AND MAXIMA OF 25-50MM/DAY THROUGH 36
HRS...DECREASING TO 10-15MM/DAY AND MAXIMA OF 20-40MM BY 48-84
HRS. OTHER ACTIVITY IS EXPECTED OVER NORTHERN COLOMBIA INTO
NORTHWEST VENEZUELA. EARLY IN THE CYCLE THIS WILL PEAK AT
25-50MM/DAY...BUT THROUGH 48-72 HRS IT WILL DECREASE TO
20-35MM/DAY.

OVER THE TROPICAL ATLANTIC...A PERTURBATION IN THE TRADE WIND
EASTERLIES ENTERED AMAPA IN BRASIL-FRENCH GUIANA...AND IT IS TO
CONTINUE WEST INTO SOUTHERN AMAZONIA IN VENEZUELA BY 48-60 HRS.
THIS IS TO INTERACT WITH THE NEAR EQUATORIAL TROUGH TO FAVOR
RAINFALL AMOUNTS OF 10-15MM/DAY AND MAXIMA OF 20-45MM/DAY. THIS
WILL DECREASE TO 05-10MM/DAY AND MAXIMA OF 15-20MM/DAY BY 48-84
HRS.

MARINERO...DGOA/MARN (EL SALVADOR)
SOLORZANO...SMN (HONDURAS)
DAVISON...HPC (USA)

SATELLITE WATER VAPOR IMAGERY REVEALS THE MID/UPPER RIDGE OVER THE
EASTERN CARIBBEAN EXPANDING TOWARD THE NORTHWEST. SYNOPTIC MODELS
SUGGEST THAT THE MID/UPPER RIDGE WILL REACH IT MAXIMUM AMPLITUDE
TONIGHT. THIS RIDGE PATTERN ALOFT WILL FAVOR THE EROSION OF THE
AVAILABLE MOISTURE ACROSS THE NORTHEAST CARIBBEAN DURING THE NEXT
COUPLE OF DAYS. GFS FORECAST SOUNDINGS SUGGEST PWAT MINIMA OF
AROUND 1.3 INCHES ON SATURDAY MORNING AS WELL AS STRONG SUBSIDENCE
CAP AROUND 850 MB. EXPECTING WEATHER CONDITIONS TO IMPROVE AND BECOME
MORE STABLE THIS EVENING THROUGH SUNDAY UNDER INFLUENCE OF THE UPPER
RIDGE AND LESS THAN NORMAL MOISTURE. FOR THE NEXT WEEK...UPPER THROUGH
WILL MOVE CLOSER TO THE REGION INCREASING THE MOISTURE AND THE
INSTABILITY ACROSS THE ISLANDS.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
315 PM AST FRI APR 27 2012

.SYNOPSIS...AT UPPER LEVELS...A STRONG RIDGE OVER THE AREA WILL
GRADUALLY DECAY THROUGH MONDAY. A WEAK TROUGH WILL CROSS THROUGH
THE AREA ON TUESDAY AND A SECOND ON FRIDAY NIGHT.

AT MID LEVELS...HIGH PRESSURE OVER PUERTO RICO AND THE U.S. VIRGIN
ISLANDS WILL FADE BUT CONTINUE OVER THE CARIBBEAN THROUGH THE NEXT WEEK.

AT LOWER LEVELS..HIGH PRESSURE OVER THE NORTHEAST CENTRAL ATLANTIC
WILL WEAKEN AND SHIFT SOUTH TODAY THROUGH WEDNESDAY. LATE MONDAY
ANOTHER HIGH PRESSURE WILL MOVE INTO THE WESTERN ATLANTIC AND
REINFORCE THE TRADE WIND PATTERN OVER THE AREA ALREADY IN PLACE.
THIS HIGH PRESSURE WILL MOVE SOUTHEAST DURING THE WEEK AND INTO
THE SOUTHEASTERN ATLANTIC BETWEEN 20 AND 30 DEGREES NORTH...
BRINGING SOUTHERLY LOW LEVEL WINDS OVER THE FOLLOWING WEEKEND.
BANDS OF MOISTURE PUNCTUATED BY A FEW DRIER AREAS WILL PASS
THROUGH THE AREA FOR AT LEAST THE NEXT 10 DAYS.


&&

.DISCUSSION...MOIST EASTERLY FLOW CONTINUED OVER PUERTO RICO AND
THE U.S. VIRGIN ISLANDS. A FEW SHOWERS FORMED AROUND THE U.S.
VIRGIN ISLANDS WHILE SCATTERED SHOWERS MOVED THROUGH PARTS OF
EASTERN PUERTO RICO IN THE MORNING. BY AFTERNOON MOST OF THE
SHOWERS HAD SHIFTED TO PUERTO RICO AND THE WATERS NORTH AND SOUTH
OF IT...WITH SHOWERS AND ISOLATED THUNDERSTORMS FORMING OVER THE
WESTERN HALF OF THE ISLAND AS IS TYPICAL FOR THE EASTERLY TRADE
WIND FLOW. EASTERLY FLOW CONTINUES WITH VARIATIONS IN THE RELATIVE
HUMIDITY THROUGH THE WEEKEND AND MUCH OF NEXT WEEK. BANDS OF
MOISTURE WILL BRING SCATTERED MORNING SHOWERS TO THE EAST AND
HEAVIER SHOWERS AND ISOLATED THUNDERSTORMS TO THE WEST PRETTY MUCH
EVERY DAY THROUGH NEXT WEEK. WHILE ONLY LIGHT AMOUNTS IN SPORADIC
SHOWERS ARE EXPECTED FOR THE U.S. VIRGIN ISLANDS. WHEN THE HIGH
PRESSURE MOVES INTO THE SOUTHEAST ATLANTIC AS DESCRIBED
ABOVE NEXT WEEKEND...FLOW AT LOWER LEVELS WILL TURN SOUTHEASTERLY...AND
SHOWERS WILL SHIFT INTO THE PATTERN SEEN MUCH OF THE FIRST PART OF
THIS WEEK...BEING HEAVIEST NORTH OF THE CORDILLERA CENTRAL AND
EAST OF SAN JUAN.


&&

.AVIATION...
PREVAILING VFR CONDITIONS WILL CONTINUE AT ALL TAF SITES...HOWEVER
BRIEF MVFR CONDITIONS WILL REMAIN POSSIBLE IN AND AROUND TJMZ AND
TJBQ IN ISOLATED TO LOCALLY SCATTERED SHOWERS THROUGH ABOUT
27/22Z. LLVL WINDS WILL BE MAINLY EAST AT 15 TO 20 KNOTS.

&&

.MARINE...DUE TO RELATIVELY TIGHT GRADIENTS OVER THE AREA AND
CONTINUED HIGH PRESSURE TO THE NORTH AND NORTHEAST...TRADE WINDS
WILL CONTINUE THROUGH AT LEAST SATURDAY OF NEXT WEEK. SEAS WILL
ALSO CONTINUE NEAR SMALL CRAFT ADVISORY CRITERION FOR AT LEAST THE
NEXT 5 DAYS.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 86 76 84 / 20 20 20 40
STT 75 86 77 87 / 20 20 20 30

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
926 PM AST FRI APR 27 2012

.SYNOPSIS...UPPER RIDGE WILL REMAIN IN CONTROL OF THE REGION
THROUGH SUN THEN FLATTEN ON MON AS UPPER TROUGH ACROSS THE YUCATAN
CHANNEL LIFTS OVER RIDGE AXIS. FRESH TRADE WINDS WILL PREVAIL INTO
MID NEXT WEEK.

&&

.DISCUSSION...LOW LEVEL MOISTURE WILL CONTINUE TO ERODE OVERNIGHT
AS HEIGHTS RISE UNDER STRENGTHENING UPPER LEVEL RIDGE.
OVERALL...VERY NICE WEATHER TOMORROW WITH JUST ISOLD SHOWERS. A SLIGHT
WEAKENING OF THE UPPER RIDGE IS EXPECTED SUN WHICH MAY ALLOW FOR
HIGHER INSTABILITY AND SLIGHTLY HIGHER POPS BUT MOISTURE REMAINS
MINIMAL. UPPER TROUGH ACROSS THE YUCATAN CHANNEL IS FORECAST TO
LIFT SLOWLY TO THE NORTHEAST OVR THE NEXT 72 HRS WITH UPPER RIDGE
WEAKENING MON. THIS WILL ALLOW FOR DEEP LAYER INSTABILITY TO
INCREASE AND THUS BETTER CHANCES FOR SHOWERS AND THUNDERSTORMS.
BROAD TROUGH WILL THEN DOMINATE THE WESTERN ATLC WITH DAILY
CHANCES OF AFTERNOON SHOWERS AND THUNDERSTORMS ACROSS WESTERN PR.
TOWARD THE END OF THE WEEK ATLC HIGH PRES WEAKENS AND SHIFTS
FURTHER EAST ALLOWING FOR WINDS TO TURN MORE SOUTHEAST AND ALLOW
DEEPER MOISTURE TO ADVECT INTO THE AREA.

&&

.AVIATION...PREVAILING VFR CONDITIONS WILL CONTINUE AT ALL TAF SITES
THE NEXT 24 HOURS. HOWEVER BRIEF MVFR CONDITIONS WILL REMAIN
POSSIBLE IN AND AROUND TIST...TNCM AND TKPK IN ISOLATED SHOWERS
THROUGH ABOUT 28/16Z. WINDS WILL BE MAINLY EAST AT 15 TO 20 KNOTS.

&&

.MARINE...TRADE WINDS WILL REMAIN IN THE 15-20 KT OVERNIGHT AND
SAT AND POSSIBLY STRENGTHEN INTO MINIMAL SCA SAT NIGHT AND EARLY
SUN. SCEC WILL PREVAIL THROUGH MON WITH MARGINAL SCA CONDITIONS
POSSIBLE SAT NIGHT AND SUN BOTH OFFSHORE ATLC AND CARIB WATERS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 77 86 77 81 / 0 10 20 30
STT 77 79 77 79 / 10 10 40 40

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
427 AM AST SAT APR 28 2012

.SYNOPSIS...UPPER RIDGE WILL REMAIN IN CONTROL OF THE REGION
THROUGH SUN THEN FLATTEN ON MONDAY AS UPPER TROUGH ACROSS THE
YUCATAN CHANNEL LIFTS OVER RIDGE AXIS. FRESH TRADE WINDS WILL
PREVAIL INTO MID NEXT WEEK.

&&

.DISCUSSION...ISOLATED LIGHT SHOWERS BRUSHED THE NORTHERN COAST OF
PUERTO RICO THROUGH THE OVERNIGHT HOURS WITHOUT GENERATING ANY
SIGNIFICANT RAINFALL ACCUMULATIONS. MORE OF THESE SHOWERS COULD
MOVE ON SHORE AND AFFECT THE NORTHEAST COASTAL REGION THROUGH MID
MORNING. MOSTLY SUNNY CONDITIONS WILL PREVAIL FOR THE MOST PART OF
THE MORNING HOURS. SATELLITE IMAGES ARE SHOWING AN AREA OF LOW
LEVEL MOISTURE NOW LOCATED OVER THE ANEGADA PASSAGE. THIS ARE IS
EXPECTED TO MOVE ACROSS THE USVI BEFORE MID MORNING...GENERATING A
FEW PASSING SHOWERS ACROSS THE LOCAL ISLANDS. THIS MOISTURE AREA
WILL BE MOVING ACROSS THE ISLAND OF PUERTO RICO BEFORE NOON.
LINGERING MOISTURE IN COMBINATION WITH DIURNAL HEATING AND SEA
BREEZE WILL GENERATE ISOLATED TO LOCALLY SCATTERED SHOWERS OVER
THE WEST AND SOUTHWEST PORTIONS OF PUERTO RICO.

UPPER TROUGH ACROSS THE YUCATAN CHANNEL IS FORECAST TO
LIFT SLOWLY TO THE NORTHEAST OVER THE NEXT 72 HRS WITH UPPER RIDGE
WEAKENING ON MONDAY. THIS WILL ALLOW FOR DEEP LAYER INSTABILITY
TO INCREASE AND THEREFORE BETTER CHANCES FOR SHOWERS AND
THUNDERSTORMS THROUGH THE END OF THE WEEK.

&&

.AVIATION...VFR CONDITIONS WILL CONTINUE ACROSS ALL TAF SITES
THROUGH AT LEAST 28/18Z. BETWEEN 28/18Z-28/22Z...PERIODS OF MVFR
CONDITIONS WITH MOUNTAIN OBSCURATION CAN BE EXPECTED OVER TJMZ
SHRA/TSRA. WINDS WILL BE MAINLY EAST AT 10 TO 15 KNOTS WITH HIGHER
GUSTS IN COASTAL AREAS.


&&

.MARINE...WINDS WILL REMAIN IN THE 15-20 KT TODAY AND SLIGHTLY
INCREASING ON SATURDAY NIGHT. SMALL CRAFT EXERCISE CAUTION WILL PREVAIL
THROUGH MONDAY WITH MARGINAL SMALL CRAFT ADVISORY CONDITIONS
POSSIBLE SATURDAY NIGHT AND SUNDAY.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 76 86 76 / 20 20 20 10
STT 79 77 79 77 / 20 40 40 10

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
328 PM AST SAT APR 28 2012

.SYNOPSIS...AT UPPER LEVELS...A RIDGE OF HIGH PRESSURE OVER THE
LOCAL AREA WILL SLOWLY DECAY AS IT MOVES EAST. WEAK SHORT WAVE
TROUGHS WILL CROSS THROUGH FROM THE WEST...ONE ON MONDAY EVENING
AND ONE ON FRIDAY NIGHT. EACH TROUGH WILL BE PRECEDED BY A NOMINAL
INCREASE IN WINDS.

AT MID LEVELS...HIGH PRESSURE REMAINS OVER THE EASTERN CARIBBEAN
THROUGH MID WEEK NEXT WEEK AND CONTINUES AFTER THAT ACROSS MUCH OF
THE CARIBBEAN AND TROPICAL ATLANTIC. MOISTURE AT MID LEVELS
RECOVERS SOMEWHAT ON TUESDAY AND CONTINUES AT MODEST LEVELS
INTO THE SECOND WEEK OF MAY.

AT LOWER LEVELS...THE HIGHER PRESSURE TO THE NORTH DRIVING THE
MODERATE TO FRESH TRADE WINDS WILL NOT WEAKEN SIGNIFICANTLY UNTIL
LATE NEXT WEEK WHEN STRONG LOW PRESSURE SEIZES CONTROL OF THE
CENTRAL ATLANTIC AND SPLITS THE NORMAL SUB TROPICAL RIDGE TO THE
NORTH IN TWO. FLOW WILL BECOME MORE SOUTHEASTERLY NEXT WEEKEND AND
NORTH COAST TEMPERATURES WILL WARM IF MODEL SOLUTIONS HOLD.


&&

.DISCUSSION...A FEW SHOWERS DID DEVELOP IN WESTERN PUERTO RICO IN
SPITE OF THE DRIER AIR THAT MOVED INTO THE AREA FROM THE EAST AS
NOTED IN THE TPW MIMIC PRODUCT. SOME SHOWERS HAVE ALSO CONTINUED
IN THE LOCAL NORTHERN ATLANTIC WATERS AND JUST BEYOND. SATELLITE
IMAGERY SUGGESTS THAT MODEL FORECASTS OF BETTER SHOWERS WILL VERIFY
LATER TONIGHT AND TOMORROW AS A BAND OF CLOUDS WAS OBSERVED
APPROACHING AT ABOUT 20 KNOTS FROM THE NORTHEAST. NEVERTHELESS THE POPS
FORECASTS HAD TO BE TEMPERED SOMEWHAT FROM MODEL SOLUTIONS DUE TO
THE DRIER AIR. FLOW AT LOWER LEVELS WILL BE EAST NORTHEAST OR EAST
FOR A QUITE A WHILE UNTIL LOW PRESSURE DISPLACES THE HIGH IN THE
CENTRAL ATLANTIC LATE IN THE WEEK. MINIMAL CONVECTIVE ACTIVITY
WILL CONTINUE IN THE USUAL PATTERN FOR THE MOST PART UNTIL AT
LEAST TUESDAY. BETTER MOISTURE MOVES INTO THE AREA AT MID LEVELS
THEN BUT SHOWERS WILL LIKELY BECOME ONLY SCATTERED WITH SOME
HEAVIER THUNDERSTORMS DUE TO THE USUAL CONVERGENCE PATTERNS OVER
THE ISLAND. THE GFS SUGGESTS THAT THE SURFACE PRESSURE GRADIENTS
WILL ALLOW THE WINDS TO DECREASE SLOWLY SUNDAY THROUGH TUESDAY AND
AGAIN THURSDAY THROUGH NEXT SUNDAY...WITH VERY LIMITED WINDS OVER
THAT NEXT WEEKEND.

&&

.AVIATION...
PREVAILING VFR CONDITIONS WILL CONTINUE AT ALL TAF
SITES...HOWEVER BRIEF MVFR CONDITIONS WILL REMAIN POSSIBLE IN
AND AROUND TJMZ IN ISOLATED TO LOCALLY SCATTERED SHOWERS THROUGH
ABOUT 28/22Z. LLVL WINDS WILL BE MAINLY EAST AT 15 TO 20 KNOTS.

&&

.MARINE...WINDS AND SEAS WILL BEGIN TO DIMINISH ON MONDAY AND
TUESDAY AND THEN BECOME MORE TRANQUIL THURSDAY THROUGH THE END OF
NEXT WEEK. BUOY 41043 SHOWED 7 FOOT SEAS AS OF 2 PM AST AND WINDS
SHOULD BE ABLE TO HOLD THESE LEVELS FOR THE NEXT 48 TO 60 HOURS.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 76 86 76 85 / 30 30 30 20
STT 76 86 77 86 / 30 20 20 10

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SAN JUAN PR
831 PM AST SAT APR 28 2012

.SYNOPSIS...UPPER LEVEL RIDGE WILL HOLD THROUGH SUN THEN BREAK
DOWN ON MON AS UPPER TROUGH ACROSS THE YUCATAN CHANNEL LIFTS OVER
TOP OF IT. FRESH TRADE WINDS WILL WEAKEN TUE THROUGH THU.

&&

.DISCUSSION...STRONG SUBSIDENCE INVERSION IN PLACE OVR THE AREA AS
SEEN ON A 2320Z SJU ACARS SOUNDING. THIS IS NOT LIKELY TO BREAK
UNTIL MON WHEN UPPER TROUGH ACROSS THE YUCATAN WILL LIFT OUT TO
THE NORTHEAST AND BREAK DOWN THE UPPER RIDGE. ALTHOUGH THERE IS A
SLIGHT INCREASE IN LOW LEVEL MOISTURE TOMORROW DEEP CONVECTION
DOES NOT LOOK LIKELY.

BETTER CHANCES OF RAINFALL APPEAR ON TAP MID WEEK WHEN PRES
GRADIENT IS FCST TO RELAX AND WINDS DECREASE ALLOWING FOR BETTER
AFTERNOON SEA BREEZE CONVERGENCE. MID-UPPER LEVEL TROUGH WILL ALSO
ALLOW FOR DEEP LAYER INSTABILITY AND HELP FUEL SHOWERS AND
THUNDERSTORMS. MOISTURE BECOMES DEEPER NEXT WEEKEND IN A MOIST
SOUTHEAST FLOW.

AFTER MID WEEK CONDITIONS WILL BECOME MORE FAVORABLE FOR SHOWERS
TO OCCUR AS PRESSURE GRADIENT IS FORECAST TO RELAX AND WINDS DECREASE
ALLOWING FOR BETTER AFTERNOON SEA BREEZE CONVERGENCE. MID-UPPER
LEVEL TROUGH WILL ALSO ALLOW FOR DEEP LAYER INSTABILITY AND HELP
FUEL SHOWERS AND THUNDERSTORMS. MOISTURE BECOMES DEEPER NEXT
WEEKEND IN A MOIST SOUTHEAST FLOW.

IN THE LONG RANGE...THE GFS IS HAVING TROUBLE FINDING A WORKABLE
SOLUTION FRIDAY AND BEYOND AS HIGH PRESSURE SINKS FARTHER SOUTH
INTO THE CENTRAL ATLANTIC. THE GFS BEGINS DEVELOPING A LOW
PRESSURE AT THE SURFACE OVER THE EASTERN CARIBBEAN AND THE
WINDWARD ISLANDS IN CONTRAST TO PREVIOUS SOLUTIONS. THE ECMWF MAINTAINS
SOUTHEAST FLOW OVER THE AREA FROM HIGH PRESSURE TO THE EAST
NORTHEAST IN THE CENTRAL ATLANTIC. UNFORTUNATELY THESE SCENARIOS EACH
DEVELOP VERY DIFFERENT WINDS FOR PUERTO RICO WHICH WOULD CHANGE
THE RAINFALL PATTERNS. AT THIS TIME EXPECT A SOLUTION LESS EXTREME
THAN EITHER WITH EAST NORTHEAST OR EAST WINDS AND A FAIRLY
CLIMATOLOGICAL PATTERN NEXT WEEKEND. NEITHER SOLUTION WOULD BRING
ANYTHING MORE THAN SCATTERED...LOCALLY HEAVY...SHOWERS.

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SAN JUAN PR
936 PM AST SUN APR 29 2012

.SYNOPSIS...UPPER RIDGE WILL BEGIN TO BREAK DOWN OVERNIGHT AS
UPPER TROUGH ALONG 80W MOVES SLOWLY EAST. BROAD TROUGH WILL THEN
DOMINATE THE WRN/CNTRL ATLC. MODERATE TO FRESH E TRADES WILL
PERSIST THROUGH FRI.


&&

.DISCUSSION...00Z JSJ RAOB SHOWS THAT SUBSIDENCE INVERSION HAS
LIFTED/WEAKENED FROM AROUND 700 MB AT 12Z TO AROUND 660 MB.
FURTHER WEAKENING IS EXPECTED NEXT 24 HRS AS UPPER RIDGE BREAKS
DOWN AS UPPER TROUGH ALONG 80W SHEARS OUT TO THE EAST. THIS MAY
ALLOW FOR BETTER CONVECTIVE CVRG ACROSS WRN PR TOMORROW WITH A
CHANCE FOR ISOLD TSTMS. MODELS THEN SHOW SOME DRYING MON NIGHT
THROUGH TUE NIGHT AS WINDS INCREASE ONCE AGAIN. THIS COULD BE
ASSOCIATED WITH PW MINIMA OBSERVED ON BLENDED TPW IMAGERY NEAR
55W. GFS THEN SHOWS RAPID MOISTENING ON WED ALTHOUGH GFES SHOWS IT
A SLOWER PACE. TREND IN THE MODELS IS FOR SUBSTANTIAL MOISTURE
INCREASE LATER IN THE WEEK AS WINDS SLOW DOWN AND TURN TO THE
SOUTHEAST WITH BETTER SHRA/TSRA COVERAGE ESPECIALLY THU-SAT.

A BROAD AREA OF LOW PRES THEN DEVELOPS NEAR THE ABC ISLANDS NEXT
WEEKEND AND TRIES TO LIFT TO THE NORTHEAST. MODELS NOW SHOW DEEP
MOISTURE LIFTING TO THE NORTHEAST ACROSS THE LEEWARD ISLANDS AS
OPPOSED TO PR LIKE THEY WERE SHOWING A FEW DAYS AGO.


&&

.AVIATION...PREVAILING VFR CONDITIONS WILL CONTINUE AT ALL TAF SITES
WITH ISOLATED PASSING SHOWERS IN AND AROUND TISX/TIST AND TJSJ
THROUGH THE FORECAST PERIOD. MVFR/IFR CONDITIONS WILL REMAIN
POSSIBLE AT TJMZ IN SHRA/TSRA DEVELOPING ACROSS WESTERN PR BTW
30/18Z AND 30/22Z. LLVL WINDS WILL BE MAINLY EAST AT AROUND 10 KNOTS
OVERNIGHT...INCREASING TO 10 TO 15 KNOTS AND GUSTY FROM THE EAST.


&&

.MARINE...SEAS ARE STARTING TO DIMINISH AT BUOY 41043 WITH LATEST
READING AT 6.6 FEET. MODEL GUIDANCE SHOWS SEAS REMAINING AROUND 7
FEET AT FCST POINT PR NORTH UNTIL 12Z MON. WILL MONITOR BUOYS
CLOSELY NEXT HOUR AND SEE WHERE THEY ARE. OTHERWISE...EXPIRATION
TIME OF 10Z LOOKS GOOD.


&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 75 84 75 85 / 50 50 10 10
STT 76 79 76 78 / 40 40 10 10

MID TO UPPER LEVEL CONDITIONS WILL BECOME MORE FAVORABLE
FOR CONVECTIVE DEVELOPMENT BY THE END OF THE WORK WEEK AS AN UPPER LEVEL
TROUGH APPROACHES FROM THE WEST NORTHWEST. AS A RESULT...BETTER SHRA/TSRA
COVERAGE CAN BE EXPECTED ON THURSDAY THROUGH AT LEAST SATURDAY. SURFACE
HIGH PRESSURE WILL MOVE OUT OF THE NORTHEASTERN UNITED STATES AND INTO
THE WESTERN ATLANTIC. THAT WILL MAINTAIN THE MODERATE TO FRESH TRADE
WIND FLOW THROUGH MUCH OF THE OF THE WORK WEEK. WINDS WILL DIMINISH
CONSIDERABLY THURSDAY NIGHT AND BEYOND.

It looks like a sharp increase in moisture for the Eastern Caribbean in the next few days.

DISCUSSION...SOME DRYING IS EXPECTED NEXT 24 HRS FOLLOWED BY A
SHARP INCREASE IN MOISTURE TUE NIGHT AND WED AS A SFC TROF MOVES
WWD ACROSS THE LOCAL AREA. SVRL SHORTWAVE TROUGHS WILL ROTATE
ACROSS THE AREA AROUND BASE OF DEEP CUTOFF LOW ACROSS THE ATLC.
THIS IN COMBINATION WITH MOISTURE CONVERGENCE WILL RESULT IN A
SUBSTANTIAL INCREASE IN TSTM ACTIVITY THU-SUN. MOST ACTIVITY WILL
CONCENTRATE NORTH OF THE CORDILLERA AND BE VERY SLOW MOVER WITH
ACTIVITY SHIFTING MORE TO THE NORTHEAST TOWARD THE END OF THE WORK
WEEK AS STEERING WINDS BECOME MORE FROM THE WEST OR WEST
SOUTHWEST. SOUTH COAST WILL LIKELY REMAIN DRY DUE TO UNFAVORABLE
STEERING WINDS. SOME DRYING IS SUGGESTED BY GLOBAL MODELS AND
ENSEMBLES EARLY NEXT WEEK AS BROAD LOW ACROSS THE SOUTHERN
CARIBBEAN LIFTS TO THE NORTHEAST AND WINDS SHIFT TO A MORE
NORTHEASTERLY DIRECTION WITH DEEP MOISTURE GETTING SHUNTED EWD
INTO THE LEEWARD ISLANDS.

.DISCUSSION...GIVEN FLATTENING MID TO UPPER LEVEL RIDGE AND
ENCROACHING WESTERLIES FOR THE NEXT COUPLE OF DAYS...EXPECT
CONDITIONS TO GRADUALLY BECOME MORE ACTIVE. FOR TODAY...MOISTURE
IS EXPECTED TO BE SOMEWHAT LIMITED AND ALTHOUGH THERE WILL BE SOME
CLOUDINESS...SCATTERED SHOWERS AND POSSIBLY AN ISOLATED
THUNDERSTORM OR TWO...TODAY MAY END UP BEING THE BEST WEATHER DAY
OF THE NEXT 5 TO 7 DAYS. FOR TONIGHT AND WEDNESDAY...AN IMPRESSIVE
SURGE OF MOISTURE WILL ENCOMPASS THE FA FROM THE EAST SOUTHEAST...
WITH VERY GOOD 850MB-700MB THETA E ADVECTION. EXPECT A GOOD DEAL
OF CLOUDINESS...SHOWERS AND A COUPLE OF THUNDERSTORMS DURING THIS
TIME...AS LOCAL EFFECTS AND WESTERLY VENTILATION COMBINE WITH
DEEPENING MOISTURE.

THIS MOISTURE AND INCREASING INSTABILITY IS NOW FORECAST BY THE
LATEST MODEL DATA...TO GENERALLY LINGER ACROSS THE LOCAL AREA FROM
WEDNESDAY NIGHT AND THURSDAY THROUGH FRIDAY...WITH POSSIBLY SOME
SLIGHT MOISTURE REDUCTION SATURDAY...FOLLOWED BY AN INCREASE AGAIN
FOR SUNDAY AND MONDAY. AS AFOREMENTIONED SIGNIFICANT TROUGHINESS
GRADUALLY DIGS AND ALIGNS TO THE WEST THROUGH NORTHWEST OF THE
LOCAL AREA DURING THIS TIME...MOISTURE AND INSTABILITY STUCK
ACROSS THE FA WILL SPELL TROUBLE...AS LOCAL EFFECTS COMBINE WITH
THIS MOIST AND UNSTABLE AIR MASS AND INCREASINGLY FAVORABLE
DYNAMICS...TO PRODUCE A RATHER ACTIVE PATTERN...WITH SEVERAL
ROUNDS OF CLOUDINESS...SHOWERS AND A FEW THUNDERSTORMS EXPECTED.
IT IS TOO EARLY TO BE CONFIDENT...BUT THIS PATTERN EVOLUTION WILL
BE MONITORED CLOSELY...AS PREVIOUS SCENARIOS LIKE THIS HAVE
RESULTED IN AREAS OF SIGNIFICANT RAINFALL AND SOME FLOODING ACROSS
PARTS OF THE LOCAL ISLANDS. STAY TUNED.

DISCUSSION...LATEST RADAR IMAGES THIS AFTERNOON DEPICTED ONLY FEW
SMALL AREAS OF ISOLATED TO SCATTERED SHOWERS MAINLY ACROSS THE
SURROUNDING COASTAL WATERS AND ACROSS WESTERN AND EASTERN PUERTO
RICO. AT THE SAME TIME...LATEST SATELLITE IMAGES SHOWED A LARGE
AREA OF CLOUDINESS ACROSS THE LEEWARD AND NORTHERN WINDWARD
ISLANDS MOVING WESTWARD ACROSS THE ATLANTIC AND CARIBBEAN WATERS.
THIS SURGE OF MOISTURE...EMBEDDED IN THE EASTERLY TRADE WIND
FLOW...IS EXPECTED TO MOVE ACROSS THE LOCAL ISLANDS TONIGHT AND
TOMORROW PRODUCING CLOUDINESS...SHOWERS AND A FEW THUNDERSTORMS
ACROSS THE LOCAL ISLANDS. THE GFS MODEL GUIDANCE SUGGESTS ABUNDANT
MOISTURE ACROSS THE REGION FOR THE NEXT SEVERAL DAYS. IN
FACT...PWAT VALUES WILL INCREASE FROM AROUND 1.50 INCHES OR LESS TODAY
TO 2.00 INCHES OR EVEN MORE FROM WEDNESDAY THRU AT LEAST FRIDAY.
LATEST MODEL DATA ALSO INDICATED THAT A BROAD AREA OF LOW PRESSURE
WILL DEVELOP ACROSS THE WINDWARD ISLANDS BY THE UPCOMING WEEKEND.
THIS FEATURE WILL THEN MOVE TO THE NORTHEAST ACROSS LEEWARD
ISLANDS AND POSSIBLE ACROSS THE NORTHEAST CARIBBEAN LATE IN THE
WEEKEND AND NEXT WEEK. THIS MOIST AND UNSTABLE AIR MASS AND
INCREASINGLY FAVORABLE DYNAMICS...IS EXPECTED TO PRODUCE A RATHER
ACTIVE PATTERN...WITH SEVERAL ROUNDS OF CLOUDINESS...SHOWERS AND A
FEW THUNDERSTORMS...TYPICAL FOR THIS TIME OF THE YEAR. THIS
PATTERN EVOLUTION WILL BE MONITORED CLOSELY...AS PREVIOUS
SCENARIOS LIKE THIS HAVE RESULTED IN AREAS OF SIGNIFICANT RAINFALL
AND SOME FLOODING ACROSS PARTS OF THE LOCAL ISLANDS.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1016 PM AST TUE MAY 1 2012

.UPDATE...SHOWERS AND A FEW THUNDERSTORMS ARE MOVING IN FROM THE
SOUTHEAST INTO THE LOCAL CARIBBEAN WATERS. THERE IS ABUNDANT
MOISTURE TO THE SOUTHEAST OF THE LOCAL AREA AND IT IS APPROACHING
THE AREA. THESE SCATTERED SHOWERS ARE EXPECTED TO CONTINUE TO MOVE
CLOSER TO OUR LOCAL AREA OVERNIGHT...INCREASING CLOUDINESS AND
SHOWER ACTIVITY OVER THE USVI AND EASTERN PUERTO RICO. COMPUTER
MODELS INSIST IN DEEP MOISTURE MOVING IN FROM WEDNESDAY UNTIL AT
LEAST FRIDAY...THURSDAY BEING THE DAY WITH THE MORE WIDESPREAD
SHOWERS. THE 02/00Z SOUNDING INDICATED A CONSIDERABLE INCREASE IN
MOISTURE AND INSTABILITY AT THE LOCAL AREA. IN ADDITION...FORECAST
SOUNDINGS CONTINUE TO INDICATE AN INCREASE IN MOISTURE AND INSTABILITY
OVER THE AREA WITH PRECIPITABLE WATER VALUES REACHING OVER 2.2
INCHES ON THURSDAY...CURRENTLY HOWEVER...BLENDED SATELLITE TPW
IMAGERY IS SHOWING PRECIPITABLE WATER VALUES OF OVER 2.4 INCHES TO
THE SOUTHEAST OF THE LOCAL AREA. AT THIS TIME WE EXPECT NUMEROUS
SHOWERS ON WEDNESDAY THROUGH FRIDAY WITH MOST OF THE ACTIVITY OVER
THE USVI AND THE INTERIOR AND NORTHERN PORTIONS OF PUERTO RICO.

.DISCUSSION...UNSETTLED WEATHER PATTERN IS FORECAST TO SET UP
ACROSS THE LOCAL ISLANDS BY THURSDAY AS DEEP TROPICAL MOISTURE
ASSOCIATED WITH THE AFOREMENTIONED LOW LEVEL TROUGH BEGINS TO GET
DRAWN ACROSS THE EASTERN CARIBBEAN. MOST OF THE OPERATIONAL MODELS
ARE INDICATING PRECIPITABLE VALUES ABOVE 2.2 INCHES ON THURSDAY.
THE COMBINATION OF HIGH MOISTURE CONTENT...FAVORABLE UPPER LEVEL
DYNAMICS AND LIGHT STEERING FLOW WILL RESULT INTENSE AND SLOW
MOVING SHOWERS DEVELOPING ACROSS PARTS OF THE ISLANDS. LOCAL 2KM
WRF MODEL SHOWED THE STRONGEST CONVECTION DEVELOPING ACROSS THE
INTERIOR AND NORTH SECTIONS OF PUERTO RICO ON THURSDAY AND FRIDAY
AFTERNOON. WE WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS
PATTERN...AS PREVIOUS SCENARIOS LIKE THIS HAVE RESULTED IN AREAS
OF SIGNIFICANT RAINFALL AND SOME FLOODING ACROSS PARTS OF THE
LOCAL ISLANDS. STAY TUNED.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
1001 PM AST WED MAY 2 2012

.UPDATE...SCATTERED TO LOCALLY NUMEROUS SHOWERS CONTINUE TO MOVE
ONSHORE AND AFFECT THE EASTERN PORTIONS OF PUERTO RICO. A FEW OF
THESE SHOWERS AREA AFFECTING THE U.S. VIRGIN ISLANDS. UNSTABLE
CONDITIONS WILL REMAIN THROUGH THE INCOMING WEEKEND. GENERATING
NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS ACROSS LARGE PORTIONS
OF OUR LOCAL FORECAST AREA. ON THURSDAY WILL VERY SIMILAR TO WHAT
OCCURRED TODAY...WITH MORNING SHOWERS ACROSS THE EASTERN PORTIONS
OF PUERTO RICO AND SCATTERED TO NUMEROUS SHOWERS AFFECTING THE
INTERIOR AND WESTERN PORTIONS OF THE ISLAND. ON FRIDAY...WINDS ARE
FORECAST TO DECREASE SIGNIFICANTLY...THIS WILL HELP LARGER AMOUNTS
OF RAINFALL ACCUMULATIONS OVER AREAS WITH SATURATED SOILS...
THEREFORE INCREASING THE CHANCES OF FLASH FLOODING

Hi to all. Rainy weather will continue thru the Eastern Caribbean at least thru the weekend.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
929 PM AST THU MAY 3 2012

.UPDATE...LATEST RADAR IMAGES THIS EVENING DEPICTED AREAS OF
NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS...ACROSS THE ATLANTIC
AND CARIBBEAN WATERS. HOWEVER...LIMITED SHOWERS ACTIVITY WAS
DETECTED OVER LAND AREAS. UNSTABLE CONDITIONS WILL CONTINUE ACROSS
THE FA FOR THE NEXT FEW DAYS. THE ABUNDANT MOISTURE...WILL COMBINE
TOMORROW WITH DAYTIME HEATING AND LOCAL EFFECTS TO INDUCE AGAIN A
NEW ROUND OF SCATTERED TO NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS ACROSS PARTS OF THE LOCAL ISLANDS DURING THE AFTERNOON
HOURS. SOILS ACROSS MOST OF PUERTO RICO AND THE U.S. VIRGIN ISLANDS
ARE SATURATED AND ANY ADDITIONAL RAINFALL WILL AGGRAVATED THE
MUDSLIDES IN AREAS OF STEEP TERRAIN...AND RIVERS WILL REACT QUICKLY
TO NEW RAINFALL ACCUMULATIONS. AS A RESULT..A FLASH FLOOD WATCH WILL
CONTINUE IN EFFECT FOR ALL OF PUERTO RICO...INCLUDING CULEBRA AND
VIEQUES...AND FOR ALL OF THE U.S. VIRGIN ISLANDS THROUGH TOMORROW
EVENING.

More rain is expected today in PR.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
446 AM AST FRI MAY 4 2012

.SYNOPSIS...OUR FORECAST AREA WILL CONTINUE UNDER THE INFLUENCE
OF A MID TO UPPER LEVEL TROUGH WHICH WILL INTERACT WITH DEEP
TROPICAL MOISTURE TO PRODUCE PERIODS OF SHOWERS AND A FEW
THUNDERSTORMS ACROSS PORTIONS OF THE LOCAL ISLANDS TODAY THROUGH
AT LEAST SUNDAY.

&&

.DISCUSSION...UPPER LEVEL TROUGH ACROSS THE WESTERN ATLANTIC WILL
CONTINUE TO PERSIST FOR THE NEXT FEW DAYS. MEANWHILE AT LOW
LEVELS...DEEP TROPICAL MOISTURE WILL CONTINUE TO POOL ACROSS THE
EASTERN CARIBBEAN AS A SHEAR LINE CONFLUENCE MEANDERS ACROSS THE
LOCAL AREA. THESE FEATURES WILL COMBINE WITH DIURNAL HEATING AND A
LIGHT STEERING FLOW TO RESULT IN INTENSE AND SLOW MOVING SHOWERS
AND THUNDERSTORMS. THE HEAVIEST SHOWERS ARE EXPECTED DURING THE
AFTERNOON HOURS ACROSS THE CORDILLERA CENTRAL AND THE NORTHEASTERN
QUADRANT OF PUERTO RICO TODAY THROUGH AT LEAST SUNDAY. DUE TO
ALREADY SATURATED SOILS...PROLONGED PERIODS OF MODERATE TO HEAVY
RAINFALL WILL RESULT IN RAPID RISES IN SMALL STREAMS AND CREEKS AS
WELL AS INCREASE THE POTENTIAL FOR FLASH AND RIVER FLOODING. AS A
RESULT...THE FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 8 PM AST
THIS EVENING. A GRADUAL EROSION OF DEEP TROPICAL MOISTURE IS
EXPECTED EARLY NEXT WEEK...HOWEVER AVAILABLE MOISTURE WILL COMBINE
ONCE AGAIN WITH LOCAL EFFECTS TO PRODUCE CLOUDINESS...SHOWERS AND
A FEW THUNDERSTORMS ACROSS THE LOCAL ISLANDS EACH AFTERNOON.

&&

.AVIATION...TSTMS EXPECTED TO DEVELOP ACROSS THE CENTRAL MOUNTAIN
RANGE AND MOVE GENERALLY EASTWARD AROUND 10 KNOTS. THESE MAY IMPACT
JSJ LATE IN THE DAY AND ST. THOMAS AT NIGHT AS UPPER TROUGH SWINGS
BY. CAN`T RULED OUT A POP UP TSRA AT ST. CROIX LATER TODAY WITH
AFTERNOON HEATING. BEST CHANCES FOR TSRA WILL BE AT LEEWARD ISLANDS
TERMINALS. CHANCES AT JBQ AND JMZ TOO SLIM TO MENTION ANYTHING DUE
TO UNFAVORABLE STEERING WINDS.

&&

.MARINE...TRANQUIL MARINE CONDITIONS ARE EXPECTED TO PREVAIL FOR
THE NEXT FEW DAYS WITH SEAS UP TO 5 FEET AND A GENTLE TO MODERATE
WIND FLOW.

&&

.PRELIMINARY POINT TEMPS/POPS...
SJU 86 76 84 76 / 60 20 50 40
STT 84 75 84 75 / 40 40 40 40