Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL

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FXUS62 KTBW 301129

Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
729 AM EDT FRI SEP 30 2016

30/12Z--1/12Z. Prevailing VFR although brief MVFR/LCL IFR in
VCNTY SHRA/TSRA moving east during the day. Best odds of TSRA
will be at SW FL terminals. SW winds become W at less than 10KT
except gusty near TSRA.


.Prev Discussion... /issued 346 AM EDT FRI SEP 30 2016/

SHORT TERM (Today-Saturday)...
Blocking pattern will continue over the eastern U.S. and western
Atlantic today as a strong cutoff U/L low persists over the
Tennessee Valley with a strong U/L ridge over the western
Atlantic. Blocking pattern will begin to break down on Saturday as
the U/L low gradually fills and lifts slowly northeast toward the
Great Lakes region...however the U/L ridge will remain over the
western Atlantic but will begin to shift a bit east late in the

At the surface, a frontal boundary will stall across north Florida
with much drier air surface and aloft sinking over the northern
nature coast with dew points dipping into the mid 50s this
afternoon. Southwest flow will continue south of the boundary across
the remainder of west central and southwest Florida with deep
tropical moisture remaining in place.  Scattered showers and
thunderstorms will develop over the coastal waters early this
morning and will push onshore mainly south of the Tampa area, and
push inland through the day.

Transition day on Saturday as broad easterly boundary layer flow
develops across the forecast area.  Deep tropical moisture will
persist over the central and southern forecast area and will
gradually push back over the nature coast.  Easterly flow will shift
timing of scattered showers and thunderstorms to the mid to late
afternoon with greatest areal coverage over the coastal counties
from Tampa south to the Fort Myers area as the east coast sea breeze
collides with the west coast sea breeze late in the day.

LONG TERM (Saturday Night-Thursday)...
The mid/upper level cutoff low will be lifting north and northeast
and opening up early next week followed by the next trough moving
into the central states. At the surface the flow between high
pressure well to the north and Matthew to the southeast will setup
an east to northeast flow across the region early next week keeping
plenty of moisture across the region leading to scattered to
numerous mainly afternoon and evening showers and thunderstorms. By
midweek the model consensus continues to move Matthew north through
the Bahamas and east of Florida. Depending on the exact position of
the storm, our area could end up having much less rainfall coverage
due to drier air wrapping southward around the storm, but for now
will continue with climatological PoPs and wait to see how things
evolve. High temperatures will remain near normal in the mid 80s to
near 90 through the period. Overnight lows will range from the mid
60s far north to mid 70s near the coast from around Tampa Bay
southward Saturday night then returning to mostly the 70s for the
rest of the period. However, if drier air does move south during
midweek low temperatures could be a few degrees cooler.

Weak surface high pressure will remain over the waters with winds
less than 15 knots and seas less than 4 feet through Monday.
Gradient will likely tighten over the waters Tuesday and
Wednesday with SCA conditions possible.

High dew points across west central and southwest Florida will
keep minimum afternoon relative humidity values above critical
levels each day. Drier air over the northern nature coast will
allow afternoon relative humidity values to drop into the upper
30s to lower 40s mainly across Levy county.


.Preliminary Point Temps/PoPs...
TPA  87  72  88  75 /  40  10  40  30
FMY  88  74  90  74 /  60  30  50  30
GIF  88  71  88  73 /  50  30  40  30
SRQ  87  73  88  74 /  40  20  40  30
BKV  88  66  88  70 /  40  10  30  20
SPG  87  75  87  76 /  40  20  40  30


.TBW Watches/Warnings/Advisories...
FL...Beach Hazards Statement through Saturday evening for
     Coastal Charlotte-Coastal Lee-Coastal Manatee-Coastal

Gulf waters...None.


LONG TERM...69/Close is the U.S. government's official web portal to all federal, state and local government web resources and services.