892
FXUS62 KTBW 181213
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
813 AM EDT Mon Aug 18 2025

...New UPDATE, AVIATION...

.UPDATE...
Issued at 811 AM EDT Mon Aug 18 2025

Water vapor satellite imagery shows some drier air across most of
the FL peninsula this morning, leading to a quiet start to the
day with very few clouds. Early 12Z sounding data suggests that
this drier air is elevated, with ample moisture in the column
through 500mb. The T/Td spread is fairly consistent and lacks any
notable dry pockets through this level. The latest TPA ACARS
sounding shows a PWAT of around 2 inches, with a consistent
profile to that of the balloon data.

Overall, this supports scattered to numerous shower and thunderstorm
activity beginning as the sea breeze initiates in the the early
afternoon. The first thunderstorms will develop near the coast,
slowly propagating inland as the sea breeze pushes east. Eventually,
these boundaries will collide somewhere over the center of the
state, with the highest concentration of thunderstorms expected over
Central Florida. Closer to the coast, some outflow boundaries could
push back west as storms collapse, and that could lead to a
secondary window for some additional thunderstorms into the evening.

Overall, the forecast looks on track. A mostly sunny, humid morning
will give way to a hot afternoon with thunderstorms. The only
adjustment was to adjust rain chances slightly, to reflect some
tweaks to timing and coverage. No additional changes are anticipated
before the afternoon.

&&

.AVIATION...
(12Z TAFS)
Issued at 811 AM EDT Mon Aug 18 2025

Thunderstorms remain the primary aviation impact, with coastal sites
seeing thunderstorms first before most of the activity consolidates
over the interior. However, complex boundary interactions could lead
to additional thunderstorms to develop and meander towards the coast
closer to sunset. This is most likely around the Tampa Bay area,
where mention of thunderstorms is the longest. However, it cannot
completely be ruled out in SWFL either. As the flow shifts more NE
tomorrow with Erin passing to the east of FL, the potential for
thunderstorm impacts will become lower as the window decreases
briefly, before increasing again later in the week.


&&

.DISCUSSION...
Issued at 245 AM EDT Mon Aug 18 2025

A light easterly flow will persist today with abundant moisture,
precipitable water around 2 inches, across much of the area.
Scattered showers and thunderstorms will begin to pop up around
midday/early afternoon near the coast as daytime heating combines
with the developing sea breeze. The convection will becoming more
numerous over inland areas during the mid to late afternoon and
early evening along the sea breezes and outflow boundaries. With
the flow remaining light the showers and thunderstorms will move
rather slow and propagate along outflow boundaries with locally
heavy rainfall possible.

The flow will turn more northeast to north on Tuesday and then
more north to northwest on Wednesday as Erin moves north off the
southeast U.S. coast. Abundant moisture will hang around for
Tuesday, but with the flow being a little stronger the highest
rain chances will be closer to the west coast and across southwest
Florida where the moisture will be the deepest. On Wednesday some
drier air will move into the region delaying the onset of most of
the convection, but by late afternoon and evening we should see
scattered to numerous showers and thunderstorms once again, but
the highest PoPs will be over the interior and eastern half of the
Florida peninsula.

For Thursday through Sunday we`ll continue to have plenty of
moisture across the area, but with the flow turning more west to
southwest the timing of the convection will shift. Isolated to
scattered convection will be possible during the late night and
morning over the coastal waters and near the coast then moving
inland and becoming more numerous over the interior and eastern
half of the Florida peninsula during the afternoon and evening
hours each day.

&&

.MARINE...
Issued at 245 AM EDT Mon Aug 18 2025

Light winds and seas continue with high pressure directly
overhead. However, some thunderstorms should be expected near and
along the coast during the afternoon and evening, with additional
thunderstorms forming offshore overnight and during the morning
hours. By midweek the flow will shift to northeast and then to
west to southwest late in the week, with a slight increase in
winds and seas likely. Scattered thunderstorms will remain
possible which could cause locally higher winds and seas.

&&

.FIRE WEATHER...
Issued at 245 AM EDT Mon Aug 18 2025

A hot and humid airmass will continue to support scattered to
numerous thunderstorms each day. The driest day this week looks to
be Wednesday before moisture again increases late in the week.
This will be due to a stronger northeast flow that will have the
potential to also create conditions favorable for higher
dispersions. There are no significant fire weather concerns at
this time

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA  94  80  94  79 /  50  40  40  20
FMY  95  77  94  78 /  50  30  50  20
GIF  95  77  95  76 /  70  60  40  10
SRQ  93  76  93  77 /  40  20  40  20
BKV  93  74  94  73 /  60  40  30  10
SPG  91  79  91  79 /  50  20  40  20

&&

Sea Breeze Thunderstorm Regime For Monday: 1
Sea Breeze Thunderstorm Regime For Tuesday: 2

For additional information on sea breeze regimes, go to:
     https://www.weather.gov/tbw/ThunderstormClimatology

&&

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...None.
Gulf waters...None.

&&

$$

UPDATE/AVIATION...Flannery
PREVIOUS DISCUSSION...Close