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000
FXUS62 KTBW 211905
AFDTBW

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
305 PM EDT Fri Jul 21 2017

.SHORT TERM (This afternoon - Saturday)...
Aloft - a low across northern Fl this afternoon moves westward...
along or just off the central Gulf coast while a ridge builds in
across south FL and Cuba from the Atlantic by late Sat afternoon.
Surface - A broad and relaxed ridge of high pressure in the Atlantic
near 30 North/60 West reaches westward to the western Gulf coast...
with an axis that meanders through southern FL. these features will
provide 1000-700MB southwesterly flow and ample moisture. Model PWAT
values run 1.8 to over 2 inches.

The rest of this afternoon will be somewhat similar to yesterday.
However the upper low with it/s cooler temperatures have helped to
fire convection earlier today and will support more robust storms.
Some small hail reports have already starting coming in. Except most
showers/storms to push inland during the rest of the afternoon and
dissipate. Although a few of them may drift back toward the Gulf or
form along outflow boundaries in the late afternoon or early evening
and end near sunset. Storms will form later tonight and again
push onshore in the morning then inland in the afternoon with
increased coverage...thanks to the continued southwesterly flow.
The upper low pulls away to the west Sat with a little less
instability for the area...lowering the chances of stronger
storms.

.LONG TERM (Saturday Night-Friday)...
High pressure ridge axis will remain across south Florida through
Monday, then lift a bit north for the first half of next week,
then get pushed south again for the end of the week. This will
keep a west to southwest flow over the area for much of the
period, with the only exception being some E/SE flow across the
southern zones early next week when the ridge axis shifts north.
Mainly scattered thunderstorms will be possible through the
period, with more morning storms possible near the coast, and then
transitioning inland in the afternoon. Waterspouts will also be
possible in the light SW flow. Nighttime temperatures will be warm
with lows in the mid 70s inland to around 80 near the coast.
Highs will be near normal with upper 80s to lower 90s.

&&

.AVIATION...
21/18Z TAFs. Mainly VFR conditions as VCNTY TSRA with FEW to SCT CB
push inland through the afternoon...but may drift back toward the
coast around sunset as they dissipate. The best chances for brief
MVFR/IFR conditions will be earlier in the afternoon. Winds are or
will shortly become SW to W for the afternoon then light and
variable overnight. Late night TSRA on the Gulf may begin to impact
coastal terminals AFT sunrise.

&&

.MARINE...
A relaxed ridge of high pressure resides across the waters into next
week...with an axis that meanders across south and central FL. Winds
and seas remain benign although higher in the vicinity of
thunderstorms...with the most likely time during the overnight and
morning hours.

&&

.FIRE WEATHER...
A moist air mass will continue with daily showers and thunderstorms
and also maintain relative humidity values above critical levels.

&&

.Preliminary Point Temps/PoPs...
TPA  79  89  78  90 /  20  30  20  50
FMY  76  90  77  92 /  10  30  10  20
GIF  75  91  75  91 /  20  50  10  50
SRQ  78  90  77  90 /  10  30  20  40
BKV  74  90  74  89 /  20  40  30  50
SPG  80  88  79  89 /  10  30  30  50

&&

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

$$

SHORT TERM/AVIATION/MARINE/FIRE WEATHER...09/Rude
LONG TERM/DECISION SUPPORT...24/Hubbard