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fxus62 ktbw 200759 
afdtbw 


Area forecast discussion 
National Weather Service Tampa Bay Ruskin Florida 
259 am EST Thursday Nov 20 2008 


Short term (today-sat)...another cold start this morning with dry 
northwest flow aloft and weak surface high centered over the area. Temperatures to 
warm today but remain about 8-10 degrees below normal with light 
westerly flow developing off the Gulf. Vorticity maximum moving through the 
deep south tonight to push surface dry cold front into the area 
overnight with temperatures warmer temperatures but still 10 degrees cooler than 
normal. Front to pass over the northern areas Friday morning into 
southern areas Friday afternoon upper trough not as deep as previous 
one so surface high pressure will build into the deep south and 
remain north over the area. Dry conditions continue as temperatures remain 
cool Fri-Sat. 


Long term (saturday night - wednesday)...the period begins with 
a flattening upper ridge over the SW U.S. And a short wave trough 
across the Ohio Valley while at the surface high pressure dominates 
the middle-Atlantic and southeast states. The short wave trough tracks 
eastward during the rest of the weekend with the surface high 
sliding offshore but continuing to ridge back to the Gulf. 


For Monday and Tuesday...a deepening trough moves along the Canadian/U.S. 
Border into the upper Great Lakes as it's surface reflection trails 
a cold front southward to the Gulf. On Tuesday the low is over the lower 
Great Lakes with the front sweeping across the East Gulf and Florida. 


By Wednesday...the low is over New England with the front well east of the 
state. An upper ridge is building over the Western Plains as high 
pressure settles in over the Gulf Coast from the northern plains. 


The forecast to remain dry with NE and east flow moderating 
temperatures back to near normal by Monday. Then the front moves 
through Tuesday and Tuesday evening with a slight chance of showers and 
an increase in clouds. Winds shift to northerly Wednesday as the front 
exits and the high builds in over the Gulf with clearing skies and 
temperatures dropping below average a few degrees. 


&& 


Aviation (20/06z - 21/06z)...VFR. Light NE winds this morning back 
to west and northwest today as high pressure shifts out over the Gulf. Sky clear 
prevails although there may some afternoon cu/stratocu. 


&& 


Marine...weak ridge axis to stretch over the East Gulf today for 
light westerly winds and small seas. Cold front to move into the 
Gulf overnight then through the East Gulf Friday with high pressure 
building into the region on breezy northerly winds quickly 
increasing seas into headlines criteria. High pressure center 
remains north of the area but tight gradient to keep NE winds and seas 
elevated Friday nt-Sat then east Sunday. Gradient finally relaxes late 
sun into Monday. 


&& 


Fire weather...dry airmass to remain over the area today. Westerly 
flow to keep min rhs just above critical levels along coastal zones 
but interior areas to see long durations of below 35 percent rhs 
and have issued red flag warning for those interior areas. On 
Friday Post frontal Levy County to have low relative humidity for around 4 hours 
so have issued Fire Weather Watch. Dry air should remain over the 
northern zones over the weekend. 


&& 


Preliminary point temps/pops... 
tpa 68 51 68 45 / 0 0 5 5 
fmy 71 50 74 48 / 0 0 5 5 
gif 68 48 68 45 / 0 0 5 5 
srq 68 49 69 45 / 0 0 5 5 
bkv 68 40 66 35 / 0 0 5 0 
spg 67 55 67 51 / 0 0 5 5 


&& 


Tbw watches/warnings/advisories... 
Florida...red flag warning from noon today to 5 PM EST this afternoon for 
Delaware Soto-Hardee-Highlands-Polk-Sumter. 


Freeze warning until 8 am EST this morning for Citrus-Hernando- 
Levy-Sumter. 


Fire Weather Watch Friday afternoon for Levy. 


Gulf waters...none. 
&& 


$$ 


Short term/marine....25/Davis 
long term/aviation...09/rude