779
FXUS62 KTBW 182349
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
749 PM EDT Wed Sep 18 2024

...New UPDATE, AVIATION...

.UPDATE...
Issued at 747 PM EDT Wed Sep 18 2024

The persistent frontal boundary is finally washing out over N FL,
but some residual convection has developed along the remnants of
this boundary and is pushing through ECFL. THis is of no factor to
our area, however. Locally, the only point of note is a few ongoing
showers across central and SWFL. With the sun now setting, much of
this activity is waning. However, moisture and instability remain
higher over SWFL and the adjacent coastal waters. Cannot completely
rule out a few overnight showers reforming off the coast,
potentially drifting inland. Thus, keeping 20 to 30% POPs for much
of the overnight.

Right at the coast through the Tampa Bay area, rain chances increase
towards tomorrow morning to around 30 to 40% with a light flow and a
weak land breeze circulation to initiate convection. Some may drift
onshore during the morning hours, quickly dissipating as they do
so as the air becomes more stable. Most of the activity for inland
areas is expected to initiate along the sea breeze later in the
day as the boundary propagates inland. The best chances are from
Manatee/Hardee/Highlands south. The flow looks light, so this will
probably be slow to occur. However, overall moisture content
remains limited and drier air continues to advect into the area in
the mid- levels. This keeps rain chances near zero for the nature
coast, with the highest POPs inland and across SWFL (50 to 60%).

The main adjustments this evening have been to update the
aforementioned POPs to reflect the current trends and expected setup
for tomorrow. Otherwise, the forecast remains on track.

&&

.DISCUSSION...
Issued at 300 PM EDT Wed Sep 18 2024

Overall forecast is unchanged for the next several days. The upper
level low over the southeast U.S. will open up and lift northeast
over the next day or so with troughing remaining along the U.S.
east coast into the weekend with ridging building over the region
early next week. At the surface the weak pressure pattern will
persist into Thursday then a weak front will move south through
the region late Thursday into Friday with high pressure building
in behind it setting up an increasing northeast to east flow
through the weekend and into early next week.

For tonight into Thursday, we will continue to see a southwest to
west flow combined with limited moisture. Isolated to scattered
convection will continue into early this evening, then wind down
later this evening. However, there could be enough lift with the
boundary moving south later tonight to allow a few showers and
possibly a thunderstorm to develop near the coast, then the
chances shift south during the day with most of the convection
over the interior and southwest Florida during the afternoon. On
Friday, the wind shift to northeast will bring some drier air into
the area, but still should be enough for isolated to scattered
afternoon and evening convection, with best chances remaining over
the interior and southwest Florida. Over the weekend and into
early next week we will continue to see enough moisture for
isolated to scattered mainly afternoon and evening showers and
thunderstorms in the northeast to east flow.

&&

.AVIATION...
(00Z TAFS)
Issued at 747 PM EDT Wed Sep 18 2024

Main concern through the TAF period will be for convection. There is
the potential for some early morning showers around TPA/PIE in the
morning, with a higher probability for showers and eventually
thunderstorms at SWFL terminals. KLAL has the least probability of
seeing storms. Outside of any convection, no significant concerns
exist. Light flow and drier limit any major concerns through the
weekend.

&&

.MARINE...
Issued at 300 PM EDT Wed Sep 18 2024

The rather light flow will continue into tonight then winds will
shift to northwest to north as a weak front moves across the
waters during Thursday. Friday through the weekend and into early
next week high pressure will build in from the north shifting the
flow to northeast to east at around 10 knots with evening surges
bumping winds up to around 15 knots, possibly exercise caution
levels early next week. Isolated to scattered showers and
thunderstorms will remain possible through the period. No
headlines are expected through the weekend.

&&

.FIRE WEATHER...
Issued at 300 PM EDT Wed Sep 18 2024

Enough moisture will remain across the region for the next few days
to allow for isolated to scattered showers and thunderstorms each
afternoon and evening. Relative humidity values will remain above
critical levels with no fire weather hazards expected.

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA  77  90  75  90 /  10  30  10  20
FMY  77  90  75  91 /  30  60  30  50
GIF  74  92  74  93 /  20  40  10  20
SRQ  76  91  75  91 /  30  40  10  30
BKV  72  91  71  91 /  10  20   0  20
SPG  80  91  79  91 /  20  30  10  20

&&

Sea Breeze Thunderstorm Regime For Thursday: 4
Sea Breeze Thunderstorm Regime For Friday: 8

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