689 
fxus61 Kiln 082036 
afdiln 


Area forecast discussion 
National Weather Service Wilmington Ohio 
436 PM EDT Friday Aug 8 2008 


Synopsis... 
high pressure over the Mississippi Valley will build southeast 
into the region tonight. An upper level low will develop over the 
Great Lakes Saturday...pushing a cold front through the region 
Saturday night. This will provide a chance of thunderstorms. 
Northwest flow aloft will continue cooler than normal temperatures 
into the new work week. 


&& 


Near term /until 6 am Saturday morning/... 
scattered-broken cumulus will continue until 23z-24z..then should dissipate. High 
pressure builds in from the northwest at the surface...but northwest flow at 500 mb will 
allow some cirrus to move across the region overnight. Mostly clear 
skies should still be the rule. 


The mav looked too cool in some locations...mainly in the S. Went 
with the moderate FWC numbers. 


&& 


Short term /6 am Saturday morning through Sunday night/... 
surface high will be centered over the region at the beginning of the 
period. Meanwhile models deepen 500 mb low and drop it into the Great 
Lakes on Saturday. NAM and GFS have trended farther south with the 
lows position. In addition to the low models push a cold front through 
the region Sat night. NGM is the quickest in pushing convection 
the region Sat. Best left seems to stay to the north...so continued to 
leave Sat dry. 


As fnt pushes through the region...expect scattered convection. Increases 
probability of precipitation to 40 in the NE...tapering them back to 20 in the west and SW. 


Surface high builds in for Sunday. With more southern position of the 500 mb 
low...should see a reinforcement of cooler/drier air for Sunday. 


Continued trend of stay below mav for high on Sat. Leaned towards 
the cooler guidance. With clouds and precipitation moving through Saturday 
night...went towards the warmer met numbers. 




&& 


Long term /Monday through Thursday/... 
with a little greater run to run consistency...am following closer 
to the European model (ecmwf) through the extended. GFS ensembles are really all over 
the place by middle week...with latest operational GFS just coming 
slightly more in line with European model (ecmwf). That being said...the northwest flow 
pattern will continue as first one then a second deep upper level low 
rotates through the NE US/eastern Ontario/western Quebec from Monday 
through late Wednesday. So continued below normal temperatures and better chance 
of precipitation with this pattern mostly in the northern and eastern 
forecast area....then dry for Friday as the low finally pulls NE. 


&& 


Aviation /19z Friday through Wednesday/... 
primarily VFR conditions will prevail for the taf sites throughout 
the forecast period...as high pressure builds in from the west. The 
lone exception will be luk...where calm winds and a 1-2 degree dew 
pt depression overnight will allow for MVFR visibilities during the pre- 
dawn hours. With a lack of surface moisture...backed off a bit from mav 
and met guidance which went with much lower visibilities overnight at 
luk. On Saturday afternoon a scattered-broken cloud deck will develop as it 
has today. 


Outlook...no significant weather expected. 


&& 


Iln watches/warnings/advisories... 
Ohio...none. 
Kentucky...none. 
In...none. 


&& 


$$ 
Synopsis...sites 
near term...sites 
short term...sites 
long term...Parker 
aviation...woodrum