Area Forecast Discussion
Issued by NWS Tampa Bay Area, FL
FXUS62 KTBW 221918
Area Forecast Discussion
National Weather Service Tampa Bay Ruskin FL
218 PM EST Wed Feb 22 2017
.SHORT TERM (Tonight - Thursday)...
Models and water vapor imagery are depicting a closed upper low
south of the Florida panhandle in the northeast corner of the Gulf
of Mexico. Models show this low moving east-southeast through the
short term period and will be located over the Bahamas by Thursday
night. Upper level ridging will build back over the Gulf of Mexico
behind this low.
The surface low is located just off the Nature Coast and extends a
frontal boundary south along the west coast of Florida. Radar
imagery and visible satellite loops are showing 2 distinct areas of
cloudiness and rain showers. The initial band has moved well inland
and is only affecting the eastern portions of Polk and Highlands
counties in our CWA. The secondary band is located over the coastal
waters and extends southeast making landfall in Sarasota, Charlotte
and Lee counties. The latest HRRR guidance shows most of these
showers and stray storms moving north-northeast through the late
afternoon/evening and will clear most of the area by midnight.
Lingering cloudiness and a stray shower can`t be ruled out through
Thursday morning, but most of the area should be rain free on
Thursday, with the highest chances of rain over the inland counties.
As for temperatures, some areas have warmed up to average temps in
breaks in cloudiness, while others have remained a few degrees cooler
under cloudy skies. Warm and above average temps will be back on
Thursday with daytime highs in the mid to upper 70s.
.MID-LONG TERM (Thursday Night-Wednesday)...
Models in good agreement with fairly benign weather conditions as
upper low weakens and lifts through the Western Atlantic by this
weekend as upper ridging from the N Carib nudges into the region
Sunday through early next week.
Weak surface high pressure over the area into Saturday with little
cloud cover and warm average temps about 5-10 degrees above normal.
A weak and mainly dry cold front to move across the Florida
peninsula Saturday night, with limited moisture and upper support.
Even post fropa, Sunday temps still only drop to around normal
levels on moderately breezy and dry northerly winds. Next week, high
pressure builds back over the region with temps and humidity again
22/18Z-23/18Z. TAFS will remain overall VFR through the period.
However, can`t rule out a brief period of MVFR for lows CIGS and
SHRA for KSRQ northward through 21Z. The biggest impact has been
gusty winds today, with some of the northern terminals gusting to
near 30 knots. Winds are expected to decrease after 00Z with winds
expected to be 10 knots or less. conditions will begin to improve
between 00-03Z with VFR conditions and no other aviation impacts
Showers and stray storms associated with a frontal boundary continue
to move through the coastal waters through the evening hours. Winds
will remain variable at 15 knots or less through the evening, then
becoming north-northwest behind the front later tonight. A brief
increasing in winds can be expected mid morning on Thursday with
winds approaching 15-18 knots, but staying below advisory level.
Seas this evening through Thursday will run around 3-4 feet and then
begin to abate late Thursday. High pressure builds in across the
area Thursday and continues until Saturday when a dry cold front
sweeps across the Gulf...followed by slightly more robust high
pressure on Sunday.
Humidity values are expected to stay well above any critical weather
weather level through Saturday. High pressure builds into the area
on Sunday and will bring in some drier air that will bring the
humidity values below 35 percent for the interior counties, but low
ERC values and winds below 15 mph should preclude any need for a red
flag warning. RH values rebound next Monday with no other fire
weather impacts expected.
.Preliminary Point Temps/PoPs...
TPA 62 78 64 80 / 40 20 10 0
FMY 59 78 63 83 / 20 10 0 0
GIF 59 78 62 83 / 50 40 10 0
SRQ 59 75 63 78 / 30 10 10 0
BKV 60 80 59 82 / 50 20 0 0
SPG 62 76 65 79 / 30 10 10 0
SHORT TERM/AVIATION/MARINE/FIRE WEATHER...74/Wynn
MID TERM/LONG TERM/DECISION SUPPORT...25/Davis