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fxus62 ktae 041802 
afdtae 


Area forecast discussion 
National Weather Service Tallahassee Florida 
202 PM EDT Friday Jul 4 2008 


Synopsis... 
so far the cumulus field has been much more suppressed than Thursday 
afternoon. As predicted by the latest run of the local WRF...the 
sea breeze fronts have much slower to propagate inland...and it 
almost seems like a type 1 sea breeze regime day (where light 
1000-700 mb mean winds allow for a slow and fairly uniform inland 
propagation of the Florida Big Bend and Panhandle sea breeze fronts). 
Deep moist convection has been rather anemic thus far...perhaps 
due to negative impact of dry air aloft on the updrafts. 


&& 


Short term... 
(tonight through monday) we expect a fairly typical Summer evening 
as scattered thunderstorms slowly diminish after sunset. Rain 
chances will only be about 30 percent...so any unlikely interruptions 
to fireworks displays will be brief. The latest numerical guidance 
forecasts an upper level trough (currently over the MS valley) to 
continue digging southward through Sunday. All guidance forecasts 
increasing deep layer moisture over our area...though moisture may 
be a bit less plentiful over our Florida zones Saturday afternoon. The 
upper trough may enhance afternoon deep moist convection as there 
will be weak q-g forcing ahead of it. Our pop forecast is based 
on a blend of climatology...MOS...and raw model output...and is 
generally in the 40 to 60 percent range. Widespread pulse severe 
storms appear unlikely due to a moderately unstable airmass and 
unremarkable vertical Theta-E gradients. Temperatures will be near 
average. 


Long term... 
(monday night through fri) the models appear to be in decent 
agreement through the extended period. On Monday the upper trough 
that has been across the region will begin to lift northeast as 
the upper ridge builds back across the area. Monday night through 
Wednesday...the European model (ecmwf) and GFS are showing an increase in deep 
layer moisture across the eastern half of the County Warning Area as a tropical 
wave tracks north around the subtropical ridge axis. Thursday 
through Friday night... the GFS/European model (ecmwf) show the upper ridge 
beginning to weaken once again and shifting south as another short 
wave trough and cold front approach the region from the northwest. 
Southwesterly flow and increasing moisture ahead of this frontal 
boundary will provide higher probabilities for shower/storm 
coverage across the area during this period. 


&& 


Aviation... 
better coverage of rain showers/ts will be over portions of northern Florida and 
southern al, and isolated over Georgia this afternoon. Therefore, have 
tempos for MVFR ceiling/visibility in thunderstorms and rain at ktlh and kdhn, and mentioned 
scattered-occasional broken cumulonimbus clouds at kaby and kvld. Outside the rain showers/ts, 
expect VFR and southwesterly winds less than 10 kts. After the convection 
dissipates later this evening, generally fair skies will prevail. 
With a moist boundary layer and near calm winds, have included 
tempos for MVFR visibility at ktlh, kaby and kvld for early Saturday 
morning. 


&& 


Marine... 
low winds and seas will continue through the week as the marine 
area remains under the influence of the Bermuda high. 


&& 


Fire weather... 
red flag conditions are not expected for the next several days. 


&& 


Preliminary point temps/pops... 
Tallahassee 71 92 71 90 71 / 30 40 30 60 30 
Panama City 75 90 75 89 74 / 30 40 30 50 30 
Dothan 72 93 72 91 72 / 30 50 30 60 30 
Albany 72 93 72 93 72 / 30 50 30 60 30 
Valdosta 70 91 70 90 71 / 30 50 30 60 30 
Cross City 70 90 70 90 71 / 30 40 30 60 30 


&& 


Tae watches/warnings/advisories... 
Alabama...none. 
Georgia...none. 
Florida...none. 
GM...none. 


&& 


$$ 


Long term...Gibbs 
aviation...jamski 
rest of discussion...Fournier