Area forecast discussion 
National Weather Service Wilmington Ohio 
659 am EDT Sat may 25 2013 


Synopsis... 
high pressure of Canadian origin will remain over the region 
for most of this weekend providing dry weather and cool temperatures. 
The high will slide east of the region by Memorial Day...with a 
chance of showers returning as a warm front approaches Sunday 
night. Temperatures will then rise above normal for the remainder 
of next week. 


&& 


Near term /until 6 PM this evening/... 
amplified middle/upper level flow pattern with a large ridge over the 
nations middle section. This places the region in northwest flow 
regime. Surface high pressure of Canadian origin...to remain across the 
Great Lakes. Skies will start out mainly clear this morning with 
rather chilly temperatures in middle 30s NE to the lower 40s SW. Will 
continue frost advisory across portion of the NE through 9 am. 


Short wave to round the upstream ridge and and then dive southeast late this 
afternoon into this evening. This combined with warm air advection will lead to an 
increase in mainly high level clouds with some middle level clouds 
developing late into the SW counties. Will continue dry forecast today 
with more favorable lift and moisture staying to our SW. Expect 
todays highs to be about 10 degrees below normal...ranging from 
the lower 60s NE to the middle/upper 60s SW. 


&& 


Short term /6 PM this evening through Monday/... 
short wave rounding upstream middle level ridge to dive southeast through lower Ohio 
Valley this evening. This combined with warm air advection will result in an 
increase in middle level clouds across the SW. Overnight low temperatures 
will range from near 40 NE to the upper 40s SW where clouds will 
be thickest. 


Weak isentropic lift develops into the far SW Sunday ahead of the 
next disturbance. At this time will leave most of the day dry and 
only continue to carry a slight chance of a shower across the far SW late 
in the day. Temperatures will moderate some on Sunday with highs 
ranging from the upper 60s NE to the lower 70s southwest. 


Next disturbance to drop southeast across Ohio Valley Sunday night/Monday. 
Numerical model differences exist regarding the timing and 
placement of associated precipitation with this feature. European model (ecmwf) has 
been most consistent taking mesoscale convective system into Ohio ahead of warm front late 
Sunday night/Monday. GFS has trended toward a drier solution and NAM 
takes this complex through ilns northwest ahead of the advancing warm front on 
Monday. Sref mean allows precipitation chances to increase across the 
entire forecast area Monday with the best threat across the west. Will trend 
forecast toward a blended solution weighted toward the sref mean/European model (ecmwf) with 
probability of precipitation increasing early on Monday but will keep probability of precipitation in chance 
category at this time due to uncertainty. Will have highest probability of precipitation 
pivot through the northwest Monday ahead of the advancing warm front. Temperatures 
will continue to moderate with highs on Monday ranging from the 
upper 60s northwest to the middle/upper 70s south. 


&& 


Long term /Monday night through Friday/... 
a warm front with showers and thunderstorms will lift north Monday 
night and early Tuesday. Showers on the north side of the feature 
will prevail but the models are showing a wide variation on when 
these start. 


On Tuesday...temperatures will be 10-15 degree warmer than Monday as 
flow turns south and warmer air of a more climatological nature gets 
pulled in. With the warmer air is higher dewpoints which will 
naturally bump nighttime lows significantly. Surface high pressure 
offshore and a mean building ridge over the eastern third of the 
country will keep highs in the low to middle 80s and lows in the lower 
60s through the remainder of next week. 


Aside from rain with the frontal passage early in the forecast...things should 
remain dry for the remainder of next week. 


&& 


Aviation /12z Saturday through Wednesday/... 
high pressure sprawled from the Great Lakes to the Tennessee 
Valley will bring VFR to taf sites. Middle and high clouds will move 
in today on a northwest upper flow. Surface winds will stay under 
10 knots from the northwest...shifting to northeast tonight ahead 
of a disturbance and developing warm front. As clouds near the 
frontal boundary thicken and lower but remain in the VFR 
range...a few showers may occur in the vicinity of day luk and cvg 
late tonight. 


Outlook...no significant weather expected. 


&& 


Iln watches/warnings/advisories... 
Ohio...frost advisory until 9 am EDT this morning for ohz046-056-064- 
065-073-074-082. 
Kentucky...none. 
In...none. 


&& 


$$ 
Synopsis...Arkansas 
near term...Arkansas 
short term...Arkansas 
long term...franks 
aviation...coniglio