773 
fxus62 kmlb 230911 
afdmlb 


Area forecast discussion 
National Weather Service Melbourne Florida 
410 am EST Monday Nov 23 2009 




..precip chances through middle week then turning drier and much 
cooler for the upcoming weekend... 


Discussion... 


Today/tonight...weak frontal boundary will stall out over central 
Florida today into tonight creating considerable cloud cover over 
much of the region. Fairly moist atmosphere will remain along this 
boundary which should be sufficient for isolated-scattered showers to develop 
over the area into the afternoon. Will keep probability of precipitation around 30% from the 
Orlando area southward where greatest moisture will exist with only 
a slight chance farther north over North Lake and Volusia counties. A 
slight chance for thunderstorms will also exist over central and 
southern portions of the east central Florida as model soundings 
show some weak instability over this area. Cloud cover will be a 
major limiting factor but if any breaks occur and allow for 
additional heating today could see a storm or two develop this 
afternoon. Weaker shear and lapse rates however should preclude any 
stronger storm development. A few lingering showers can be expected 
into this evening...especially over the south...but then should see 
all precipitation end by midnight. Elevated low level moisture and weak surface 
winds will once again make for favorable fog formation conditions 
later tonight. Will add patchy fog in the zones for now. 


Tue-Wed...weak front draped over the south Central Peninsula on 
Tuesday will begin to drift back northward by late Tuesday. This 
occurring as a surface wave develops along it over Gulf and flow 
aloft backs a little more south-southwest/increases as trough deepens into Gulf. 
This allows deeper moisture over Caribbean to be drawn northward toward 
the state. Have chance probability of precipitation in all areas for these periods with 
values trending higher on Wednesday. May need to add a thunder mention in 
southern areas near boundary Tuesday afternoon if later runs indicate the 
presence of the boundary and weak disturbance aloft will be able to 
overcome marg instability. On Wednesday...the middle level jetstreak/vorticity 
energy look a little stronger and thunder mention may be needed all 
areas if this trend holds through later runs. 


Wednesday nite-Thanksgiving...surface low along old frontal boundary will 
approach the southern Florida Peninsula late Wednesday/Thursday morning. The low 
will lift NE over Atlantic by late in the day Thanksgiving with 
strong push of cooler/drier air spreading down the peninsula behind 
it. Showed a north-S pop striation Thursday...with higher chances early in 
the day and across the south. Maxes on Thanksgiving ranging from middle 
70s north to around 80 in the south. 


Fri-sun...drier and much cooler air mass becomes entrenched over the 
region Friday. Maximum temperatures will top out in the middle 60s north-lower 70s 
south Friday. Overnight lows expected to be in the 40s over most of the 
area and maybe a few upper 30s cooler northern interior by Sat morning. 
The cool temperatures will persist through much of the weekend with surface 
high center not moving offshore over Atlantic until Sunday night. 


&& 


Aviation...patchy fog/low stratus will make for IFR/MVFR 
conds...especially over north terminals through early this morning but 
should then see predominate VFR conds by middle/late morning. Isolated-scattered 
rain showers possible this afternoon along stalled frontal boundary over the 
area which could create tempo MVFR conds. Will only mention vcsh 
though for now as coverage looks low. A slight chance for thunderstorms and rain will 
also exist but due to the lower chances will also not mention in the 
tafs at this time. 


&& 


Marine...weaker and more variable winds will exist across the 
coastal waters today into tonight as weak surface front stalls over 
central Florida. Seas will continue a gradual decline with east/NE 
swells keeping seas up to 5 feet offshore today and then diminishing 
to at or below 4 feet tonight. A slight chance for offshore moving storms will 
exist along the nearshore waters from Brevard County southward this 
afternoon...however environment is not favorable for any stronger 
storm development. 


Tue-Fri...winds at or below 10kt through middle week with weak frontal boundary 
drifting over waters. Winds will increase Thursday with passage of 
surface low center to the south followed by strong northerly surge 
late Thursday into Friday....and headlines will be likely by late Thursday. 


&& 


Preliminary point temps/pops... 
dab 78 64 76 65 / 20 10 30 30 
mco 80 64 81 65 / 30 20 30 30 
mlb 80 64 80 68 / 30 20 30 30 
vrb 80 63 82 69 / 30 20 30 30 
Lee 80 62 77 64 / 20 10 30 30 
sfb 80 63 80 64 / 30 10 30 30 
orl 80 65 81 65 / 30 20 30 30 
fpr 80 64 82 68 / 30 20 30 30 


&& 


Mlb watches/warnings/advisories... 
Florida...none. 
Am...none. 
&& 


$$ 


Short term/aviation...weitlich 
long term....glitto