Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL
FXUS62 KTBW 270746 CCA
Area Forecast Discussion...corrected
National Weather Service
Tampa Bay Ruskin FL
336 AM EDT SAT AUG 27 2016
Includes a correct mid/long term section
.SHORT TERM (Today and Sunday)...
Broad upper troughing extends from southern Canada southward into
the Northern and Central Plains ans Rockies regions, with upper
ridging from the western Atlantic into the southeastern U.S. To
the south of this feature, weak ridging extends across the Gulf of
Mexico, with an open wave near Cuba. This feature will be the
primary focus over the next couple of days.
For today, expect very similar conditions to yesterday. Surface
ridging remains anchored to the north, with persistent easterly
low level flow across the Gulf Coastal region. Scattered showers
and a few storms will continue to linger offshore through the
morning hours, with a stray shower or two possible inland. Given
the abundant moisture present across central and southern Florida,
it wont take much heating to get showers and storms going today,
and expect development by late morning and early afternoon.
Activity will develop first over eastern and interior Florida,
shifting westward and increasing in coverage through the evening
hours. The areas most likely to see rain will reside south of I-4
along the Suncoast. Given PWATs in excess of 2 inches, locally
heavy rainfall will be likely with stronger storms.
Storms look to shift offshore tonight with perhaps a stray shower
or two over mainly southern Florida nearer the deeper moisture.
By Sunday, models show a tropical wave, Invest 99L, approaching
the southeast Florida peninsula and Florida Keys. Over the last
few days, short and medium range guidance has suggested a downward
trend in terms of the potential for this system to develop into a
tropical depression or storm. That is not to say there is zero
chance, but at this time, the most reliable models maintain a weak
tropical wave through the weekend. However, the approach of this
system will signal an increase in the potential for heavy rain
across south Florida, and perhaps a few east to west oriented
bands of heavier rain and thunderstorms mainly south of I-4. At
this time, even the flooding threat appears limited, and no real
wind impacts are expect inland. We will continue to monitor this
system as it emerges into the Gulf sometime late Sunday, but for
now, it appears the main impact will be for a rather damp weekend
across southern Florida.
Temperatures look to remain near seasonal normals with highs in
the low 90s and slightly cooler south where clouds and rain occur.
Lows will generally remain in the mid 70s inland with upper 70s to
low 80s near the coast.
.MID/LONG TERM (Sunday Night-Friday)...
The National Hurricane Center continues to monitor an area of low
pressure in the central Bahamas...among others. Please see
WWW.NHC.NOAA.GOV for details on all features tracked. The models
have a large spread in the track and strength of this low plus have
had poor run to run consistency.
However...the general model trends are for the low to slowly move
through the straits south of the keys MON...over the east central
gulf midweek...then into the northeast Gulf for weeks end. This
track advects deep tropical across the area and maintains it through
much of the period. Resulting in scattered to numerous showers and
isolated to scattered thunderstorms with heavy rainfall and the
treat of localized flooding. The rainfall and clouds will help keep
high running below normal. With much uncertainty in the future of
this system will adjust the forecasts as necessary.
.AVIATION (06z TAFs)...
Most shower activity has shifted offshore early this morning,
though a stray shower or two may still occur most anywhere from
KLAL to KTPA south. Mainly VFR conditions expected for the rest of
the night. Expect another batch of storms to develop by 15z today
and move westward, with impacts to virtually any terminal through
the evening hours. Therefore, will maintain VCTS with better odds
of impacts to VSBYS/CIGS from KPGD south. Storms to move offshore
by 03z Sun.
High pressure remains anchored to the north of the waters, with
persistent east to northeast flow. This will continue to favor
easterly surges of wind during the overnight and early morning
hours each day, with winds approaching 15 to 20 knots...and waves
of 2 to 4 feet. From Sunday into early next week, a tropical wave
will move into the southeastern Gulf of Mexico, resulting in a
slightly tighter gradient and perhaps increased winds and seas
offshore. Some tropical development may occur with this wave early
in the week as it lifts northwestward toward the central Gulf of
Mexico. Additionally, as the wave approaches, waves of shower and
thunderstorm activity will be likely, which may locally enhance
winds and seas.
Seasonably moist conditions will persist into next week with
daily chances for rain. This will maintain relatively high
afternoon humidities through next week and no fire weather
concerns are expected.
.Preliminary Point Temps/PoPs...
TPA 91 77 91 77 / 40 20 40 20
FMY 91 77 89 76 / 60 20 70 30
GIF 92 75 90 75 / 40 10 40 10
SRQ 91 76 91 77 / 60 30 50 30
BKV 93 75 91 75 / 40 20 40 10
SPG 90 79 91 79 / 50 20 40 20
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...84/Austin
MID TERM/LONG TERM/DECISION SUPPORT...09/Rude