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Area Forecast Discussion (AFD)

Issued by Tampa Bay Area, FL (TBW)

FXUS62 KTBW 171737

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
137 PM EDT Tue Sep 17 2019

An upper-level ridge that has been created in part by Humberto and a 
tropical wave in the Western Gulf will be replaced by a positively 
tilted upper-level trough axis as it dives southward. This trough 
will serve to filter "cooler" and drier air into the area beginning 
late tomorrow night.

For this afternoon/evening, however, Humberto continues to influence 
our weather as the cyclonic (clockwise) flow brings drier, 
continental air over the region. This is not unlike conditions for 
the rest of the week, but the more comfortable conditions are still 
trapped to the north of the peninsula. Complements of diurnal 
heating, lack of rain, and fewer clouds, temps are expected to reach 
the low-to-mid 90s for almost everywhere except the immediate coast 
between now and roughly 5PM. Unlike last week where high humidity 
combined with higher temperatures reached heat advisory criteria, 
the drier air should keep temperatures feeling closer to the actual 
value. It will still feel hot, but not as hot as last week.

Thankfully, conditions will begin to transition tomorrow as the 
front makes it way through the area. A few showers are possible 
across the region, particularly tomorrow afternoon/evening. 
Temperatures will respond to this change on Thursday with highs 
reaching the mid-to-upper 80s as opposed to the lower 90s. The 
humidity levels will be the most noticeable difference, with 
conditions feeling more comfortable beginning Thursday. Winds will 
also increase with a tighter pressure and thermal gradient across 
Florida. Overall, Thursday will be a nice day across the region.


Conditions will gradually return to a late summer pattern through 
the weekend and into next week. A tropical wave passing through the 
Florida straights will also facilitate the return of moisture to 
southern portions of the peninsula. There are noticeable 
discrepancies at this point in the forecast between the global 
models, with the precipitation parameterization schemes 
struggling to determine the northward exentent of the 
precipitation. However, there has been a northward trend in 
precipitation over the last couple cycles and this may continue. 
Overall, conditions are expected to warm up and humidity/moisture 
levels will begin to return early next week.


VFR conditions are expected through the forecast period. Winds will 
become light and variable overnight and then light northeast on 


Light northerly winds and fairly calm seas will remain through 
tomorrow evening. A round of showers are possible tomorrow night 
across offshore waters as a passing front pushes through. This front 
will lead to increasing winds and seas Wednesday night into 
Thursday. By Friday, winds and seas will be approaching cautionary, 
then advisory levels in offshore waters. Winds and seas will 
gradually settle down through the weekend. Mariners planning to boat 
on the Eastern Gulf later this week should monitor the latest 
forecast for updates on these anticipated rough conditons. 


Conditions will begin to dry out the remainder of this week. Aside 
from some low rain chances Wednesday afternoon/evening, little-to-no 
rain is expected for the next several days. While drier 
comparatively to what has been the typical weather for the last few 
months, conditions are expected to remain above critical levels. 


.Preliminary Point Temps/PoPs...
TPA  75  93  73  89 /   0  40  10  10 
FMY  74  92  73  88 /   0  40  10  10 
GIF  73  93  72  88 /   0  30   0  10 
SRQ  75  93  73  89 /   0  40  20  10 
BKV  71  93  71  89 /   0  40  10  10 
SPG  76  93  74  90 /   0  40  20  10 


Gulf waters...None.