Areal Flood Warning 7, NWS Tampa Bay, FL

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
316 AM EDT Tue Aug 3 2021

...FLOOD WATCH THROUGH WEDNESDAY EVENING FOR THE NORTH...

.SHORT TERM (Today - Wednesday)...
A long wave trough from the Great Lakes to the northern Gulf of
Mexico waters slowly eases east and south through late Wed as a
few weak embedded short wave troughs traverse through it's base.
At the surface: a nearly stationary frontal boundary resides
through midweek along the AL/GA/FL border while Atlantic high
pressure stretches into the southern Gulf waters with an axis
along the Florida Keys. A deep and very moist southwesterly to
westerly flow remains in place. Model PWAT values generally run
in the 2 inch range...up to 2.4 inches along and north of the I-4
Corridor with 2 inches or just below to the south.

This pattern will support abundant rainfall in scattered to numerous
showers and thunderstorms. These will occur just about anytime and
favor locations from around Tampa Bay northward which could see some
excessive rainfall. From Hernando and Sumter counties northward a
flood watch is now in effect and will continue into Wed night.
Temperatures will be in the lower to mid 90s except mid to upper
80s in the north...where the heaviest rainfall is expected. Heat
indices reach around 105 especially in the interior south but stay
below advisory threshold.

.LONG TERM (Wednesday night - Monday)...
An upper level trough over the eastern U.S. at the start of the
period will weaken and lift out to the northeast which will allow
mid level and surface ridging to build in from the east with the
surface ridge axis lifting northward. With the surface ridge axis
moving back to the north the southwest to west flow of late will
slowly back to the south southeast through the end of the week which
will favor timing of scattered to numerous showers and storms over
inland areas during the late morning hours, then moving west
northwest toward the Gulf coast during the afternoon and evening
hours. As we move into the weekend and continuing into early next
week consensus of models show mid level ridging building in over the
area, with the surface ridge axis lifting further to the north to
lie near the FL/GA border with the low level flow backing to the
east southeast. This flow pattern will favor the highest pops and
best convective coverage of diurnal sea breeze driven showers and
storms along and to the west of the I-75 corridor each day during
the afternoon and evening hours. Temperatures will run near seasonal
norms with overnight lows in the lower to mid 70s inland areas, and
upper 70s along the coast, with daytime highs in the lower to mid
90s each afternoon with heat indices in the 100 to 105 degree range.

&&

.AVIATION...
03/06Z-04/06Z. SCT convection to continue at/near northern terminals
through much of the period with MVFR/LCL IFR PSBL. From SRQ south
anticipate VCSH AFT 08Z then VCTS AFT 16-18Z. All locations begin to
wind down 00-04Z. Light mostly S winds become SW AOB 12KT in the
afternoon.

&&

.MARINE...
Atlantic high pressure stretching out over the Gulf of Mexico
continues...with an axis initially near the Florida Keys that lifts
northward into north FL by early next week. Southwesterly winds
gradually back through the south to become southeasterly...at light
to moderate speeds. Although winds and seas will be locally higher
near scattered to numerous showers and thunderstorms

&&

.FIRE WEATHER...
Moisture rich air resides across the fire districts for the next
several days with no low RH concerns and scattered to numerous
showers and thunderstorms...with some heavy rainfall possible.

&&

.Preliminary Point Temps/PoPs...
TPA  90  77  90  80 /  70  40  60  40
FMY  91  76  92  77 /  60  30  40  10
GIF  89  75  89  75 /  70  30  60  30
SRQ  89  77  89  77 /  50  40  50  30
BKV  87  75  87  73 /  80  50  70  50
SPG  88  78  88  80 /  70  40  60  40

&&

Sea Breeze Thunderstorm Regime For Today: 5
Sea Breeze Thunderstorm Regime For Tomorrow: 5

For Additional Information On Sea Breeze Regimes go to the link below
https://www.weather.gov/tbw/ThunderstormClimatology

&&

.TBW WATCHES/WARNINGS/ADVISORIES...
FL...Flood Watch through Wednesday evening for Coastal Citrus-Coastal
     Hernando-Coastal Levy-Coastal Pasco-Inland Citrus-Inland
     Hernando-Inland Levy-Sumter.

Gulf waters...None.
&&

SHORT TERM/AVIATION/MARINE/FIRE WEATHER...09/Rude
LONG TERM/DECISION SUPPORT...57/McMichael