551 
fxus62 ktbw 210803 
afdtbw 


Area forecast discussion 
National Weather Service Tampa Bay Ruskin Florida 
303 am EST Friday Nov 21 2008 


Short term (today-sunday)...upper trough swinging through the southeast U.S. This 
morning to push cold front over the area today with strong and dry 
high pressure building into the deep south on breezy northerly 
flow just behind front. Moisture remains very limited today so 
front passes dry as temperatures continue to run 5 to 10 degrees below 
normal. Associated airmass to filter cold temperatures into the area 
tonight and again expect to see freezing temperatures over the northern 
Nature Coast with 3+ hours in Levy County so have issued freeze 
watch there. Elsewhere over west central and SW Florida overnight cold 
overnight lows to be 10-15 degrees below normal. 


Upper flow to remain dry west-northwest-northwest over the weekend. Surface high remains 
north of the immediate areas slowly moving through the deep south Sat to 
the Carolinas sun. Low level flow veers NE with a slow moderating 
trend as temperatures remain up to 5-10 degrees below season norms. 


Long range (sunday night - thursday)...high pressure aloft and 
strong surface ridge over the eastern Seaboard will dominate the 
region with generally clear to partly cloudy skies and cool 
temperatures through Tuesday. A very weak frontal feature is still 
depicted in the models reaching the state by Tuesday afternoon...but 
latest guidance keeps the significant dynamic support for convection 
well to the north of the area. Therefore...will keep isolated/20 
percent probability of precipitation for Tuesday afternoon in the forecast and wait for the 
next model runs before making any other changes. The front is 
followed by more high pressure and a cooler airmass which remains 
firmly in place over the southeast states through the end of the 
long term. 


Temperatures remain below normals through Tuesday when a brief 
warming trend will accompany the frontal passage...but quickly dropping back 
to below normals in the wake of the front on Wednesday and beyond as 
the colder airmass descends upon the region. 


&& 


Aviation...although VFR conditions under clear skies should be the 
norm for most of the early morning hours...an area of shallow clouds 
has developed over the Easter-central Gulf waters around 2500 feet. 
These clouds are slowly into the Tampa Bay area and srq...bringing 
periods of bkn024-025. Therefore...will carry tempos over pie and 
srq through 09z. VFR should prevail on Friday with late morning and 
afternoon periods of winds in the breezy category as a front moves 
across the area. 


&& 


Marine...tight gradient and strong high pressure to build over 
the East Gulf today for elevated northerly winds and seas. High end scec 
conditions over the Bay and near shore waters and Small Craft Advisory conditions 
well offshore today into Saturday. North flow becomes NE and moderate over 
the weekend high pressure moves east and gradient slightly weakens. 
Lighter flow Monday then next front to move through the region Tuesday 
with another area of high pressure building into the Gulf. 


&& 


Fire weather...dry airmass to filter into the Nature Coast behind 
cold front late this morning into the this afternoon for relative humidity below 
35 percent with winds around 15 miles per hour for hazardous fire weather 
conditions. Have issued red flag warning for that area today. Low 
level flow to become NE Sat and sun with slightly Atlantic 
moisture increase to keep dry air over the northern Nature Coast 
with marginal durations and min rhs just above critical levels elsewhere. 


&& 


Preliminary point temps/pops... 
tpa 70 41 68 50 / 5 0 0 0 
fmy 76 47 72 52 / 5 0 0 0 
gif 69 41 67 48 / 5 0 0 0 
srq 70 43 71 50 / 5 0 0 0 
bkv 67 33 66 42 / 5 0 0 0 
spg 68 48 68 54 / 5 0 0 0 


&& 


Tbw watches/warnings/advisories... 
Florida...red flag warning from noon today to 5 PM EST this afternoon for 
Citrus-Hernando-Levy-Sumter. 


Freeze watch from late tonight through Saturday morning for Levy. 


Gulf waters...Small Craft Advisory from 10 am this morning to 10 am EST 
Saturday for Bonita Beach to Englewood out 20 to 60 nm- 
Englewood to Tarpon Springs out 20 to 60 nm-Tarpon Springs 
to Suwannee River out 20 nm-Tarpon Springs to Suwannee 
River out 20 to 60 nm. 


Small craft exercise caution from 10 am EST this morning through 
Saturday morning for Bonita Beach to Englewood out 20 nm- 
Englewood to Tarpon Springs out 20 nm-Tampa Bay waters- 
Tarpon Springs to Suwannee River out 20 nm-Tarpon Springs 
to Suwannee River out 20 to 60 nm. 


&& 


$$ 


Short term/marine....25/Davis 
long term/aviation...22/reynes