Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 291051
Area Forecast Discussion
National Weather Service Tallahassee FL
651 AM EDT Sat Apr 29 2017
.AVIATION [Through 12Z Sunday]...
IFR to LIFR conditions continue at ECP and DHN at this hour, with
VFR conditions at all other sites. Expect conditions to improve to
VFR within the next few hours at ECP and DHN. Partly cloudy
conditions expected this afternoon, with prevailing southerly
winds of 10 to 15 knots, occasionally gusting between 15 and 20
.PREV DISCUSSION [411 AM EDT]...
.NEAR TERM [Through Today]...
Deep layer high pressure remains in place across the region at this
hour. As mentioned in the evening update, a moist boundary layer
and weak surface winds will yield some patchy fog development
across the western half of the forecast area overnight. However,
dense fog is not expected.
A potent upper level low currently digging through the Southern
Rockies to emit several shortwave troughs downstream during the
day, helping to break the ridge down. This will have little effect
on the resultant weather for today outside of passing mid to high
level clouds across the region. Another warm day is on tap across
the region, with high temperatures once again reaching the upper
80s and lower 90s, especially in areas where cloud cover clears
during the morning hours.
.SHORT TERM [Tonight Through Monday]...
The broad upper trough currently over the western CONUS will
translate slowly eastward this weekend. The core of trough will be
over the upper MS Valley late Sunday night, while the attendant
surface cold front will be moving into southeast AL and the FL
Panhandle. Until then local rain chances will generally be less
than 20% (during the afternoon hours). Temperatures will be above
average with highs 85 to 90, and lows 65 to 70.
For Sunday night into Monday, there still remains a marginal risk of
severe weather, mainly across southeast Alabama and the Florida
panhandle. A squall line will be approaching the area late Sunday
night. Guidance indicates a small area of unstable air will persist
ahead of it into the far western portions of our area with
sufficient wind shear to maintain the marginal risk of mainly
damaging winds. The squall line is expected to continue gradually
weakening as it moves eastward with the severe weather threat
decreasing farther to the east.
.LONG TERM [Monday Night Through Saturday]...
There will be a brief period of fair weather Tuesday and Tuesday
night, but the synoptic pattern will become more complex mid to
late week as a positive-tilt trough develops over the lower MS
Valley and translates slowly eastward. There are some timing
differences in the guidance with the 00z GFS slower to move the
system through than the 00z ECMWF. The official forecast has a
chance of showers and thunderstorms on Wednesday through Friday
with the best chances currently centered on Thursday. Near average
temperatures are expected.
A relatively strong pressure gradient will develop across the
marine area through early Monday, with southeast to south winds
increasing to advisory levels at times, especially west of
Apalachicola. This will lead to high seas and above-normal tides.
Early indications are that peak storm tides of 2 to 3 feet are
possible along the Apalachee Bay coast, with inundation of about 1
foot along the coasts of the FL Panhandle and Big Bend Monday.
RHs will remain above critical thresholds for the next several
days, precluding red flag conditions. However, high transport
winds and elevated mixing heights will yield high dispersions
across much of the region this afternoon and again on Sunday
afternoon. Chances for wetting rains will increase late Sunday
night into Monday.
Local rivers will remain below flood stage through at least Monday
morning. Rainfall amounts will generally be in the 0.50 to 1 inch
range from Tallahassee north and westward with lesser amounts to
the south and east. Another system is likely sometime between
Wednesday and Friday with some heavier totals possible. However,
the risk of river flooding is low given the recent dry conditions
and relatively low river levels.
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 90 70 87 71 78 / 0 0 0 20 70
Panama City 88 72 80 73 74 / 0 0 0 50 80
Dothan 88 68 87 70 75 / 10 0 0 70 70
Albany 92 70 89 71 79 / 10 0 0 40 80
Valdosta 92 69 89 70 83 / 10 0 10 20 60
Cross City 92 69 91 70 83 / 0 0 10 20 30
Apalachicola 85 72 81 73 77 / 0 0 0 20 60
FL...High Rip Current Risk through late Sunday night for Coastal Bay-