Area forecast discussion 
National Weather Service Binghamton New York 
454 PM EDT Sat may 25 2013 


Synopsis... 
the northly flow of cold air will continue over the Holiday 
weekend as a low moves slowly out of New England. This will make 
for very chilly nights...with a chance for frost or freeze in some 
locations, and blustery days. The flow will relax somewhat 
allowing for a more comfortable afternoon on Monday. 


&& 


Near term /until 6 am Sunday morning/... 
models show little mvmt in the upper low tonight and actually back the 
precipitation a bit this evening as a weak upper WV rotates through. This will help 
keep clouds in the area and the winds up...in turn helping the 
frost/freeze scenario. Still...it's a tough call with the winds 
precluding frost in most areas. However...with temperatures aprchg 32f...some 
parts of the central southern tier may get spotty frost in the sheltered 
valleys where the winds become light. Does not look like enough below 
freezing temperatures to warrant a freeze warning for tonight. In any 
case...word is out and most shd be protecting their plants. 


Models were in rsnbl agreement on temperatures ldg to higher confidence. 
Cnsdrd putting some mixed pcp in the forecast but surface temperatures where the 
precipitation is falling is very mrngl...plus...temps aloft really do not 
support any frozen due to the isothermal layer in the precipitation zone. 


&& 


Short term /6 am Sunday morning through Tuesday/... 
upper low fnly begins to kick out on sun and any leftover precipitation shd 
exit the County Warning Area early. Northwest flow continues but with more sun...modification 
of the air mass shd begin in earnest on sun. Sun night may be a real 
prblm for plants with the lighter winds and very dry air in place. 
Will of course continue with the freeze watch and expect the upgrade to 
a warning as guidance indicates a wide area of upper 20s through The Heart 
of the forecast area. 


Continued imprvmt Monday after a chilly start as the high mvers ovrhd. Tuesday 
starts dry but will become cdy as the warm fnt approaches from the Ohio 
Valley. Rapidly building heights and warm air advection will help develop precipitation during tus and 
perhaps even some conv late. Fnt will mark the return of much warmer 
air for the end of the week. 


&& 


Long term /Tuesday night through Saturday/... 
surface high is 
centered off the East Coast. An upper level ridge builds over the 
eastern US from Wednesday into Saturday causing afternoon temperatures 
climb through the 80s to near 90 by the weekend. Humidity will 
also build getting US back into the feel of Summer increasing the 
instability. The question is the trigger. Do we stay suppressed or 
does a warm front stall over northern New York with a possible northwest flow 
convective pattern. Used HPC grids which follow closer to the 
European model (ecmwf) placing the front in northern New York. Warm front passed from SW 
to NE across the forecast area Wednesday with a chance of showers and 
thunderstorms. If the front stalls in northern New York than that would 
be a focus for triggering storms Thursday and Friday hence a 
little greater pop across the north. Just to note though...the GFS 
stalls the front further north in Canada and instead rotates 
scattered convection areound the west side of the surface high up 
across eastern PA into southcentral New York implying that the southern 
part of the forecast area has a greater chance. Either way it will 
likely be hot and humid with a chance of showers and 
thunderstorms. 


&& 


Aviation /21z Saturday through Thursday/... 
VFR conditions across the area are expected to continue. Scattered 
showers east of I-81 through midnight tonight should only produce 
very localized restrictions over higher terrain. After midnight 
the showers and associated clouds retreat to the east with clear 
skies to the west. Good VFR conditions expected Sunday. 


Of greater issues is likely with winds out of the northwest at 15-20 knots 
with gusts 25-30 knots this afternoon. As temperatures cool this 
evening...stronger wind gusts will subside but winds will continue 
about the inversion. Gusty winds will mix down again on Sunday but 
about 5 knots lighter than today. 


Outlook... 


Mon-Tue...VFR. 


Wed-Thu...VFR. Chance thunderstorms. 


&& 


Bgm watches/warnings/advisories... 
PA...frost advisory from 2 am to 9 am EDT Sunday for paz038>040-043- 
044-047-048-072. 
Freeze watch from late Sunday night through Monday morning for 
paz038>040-043-044-047-048-072. 
New York...frost advisory from 2 am to 9 am EDT Sunday for nyz022>025- 
044>046-055>057-062. 
Freeze watch from late Sunday night through Monday morning for 
nyz009-022>025-036-037-044>046-055>057-062. 


&& 


$$ 
Synopsis...dgm 
near term...dgm 
short term...dgm 
long term...bmw 
aviation...bmw