Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 241957
Area Forecast Discussion
National Weather Service Tallahassee FL
357 PM EDT WED AUG 24 2016
.NEAR TERM [Through Tonight]...
Numerous showers and thunderstorms were developing across the FL
Panhandle as of 2 pm EDT, where, in addition to ample deep layer
moisture, there was strong convergence between the developing sea
breeze front and the orthogonal 1000-700 mean wind. Elsewhere
convection will be spotty, as the airmass gradually dries from east
to west, as well as a lack of well-defined mesoscale boundaries.
(The FL Big Bend sea breeze front will likely stay pinned at the
We expect showers and thunderstorms to dissipate earlier this
evening than in the past several days, as the drier airmass will
promote a quicker decay of CAPE. Overnight lows will be slightly
cooler than what we`ve observed over the past several weeks- mostly
in the lower 70s inland and away from the cities.
.SHORT TERM [Thursday Through Friday Night]...
Abnormally dry air for this time of year will move into our area
during this period. PWAT values near or below 1.0" could be
present across our inland locations on Thursday, and again late
Friday night under dry northeasterly flow. As a result, most
inland locations should stay dry through this period, with slight
chances of showers and thunderstorms mainly staying offshore.
Highs will be in the low-mid 90s, with lows ranging from the upper
60s to lower 70s.
.LONG TERM [Saturday Through Wednesday]...
Unusually dry air for late August will continue across our area
during Saturday, with PWAT values remaining around 1.0". With
weak upper level flow and little to no forcing present, expect
continued dry conditions across our inland areas. On Sunday,
moisture could return to more typical levels by the afternoon, so
low chance PoPs were expanded across our area with scattered
showers and thunderstorms possible.
Attention then turns to the tropical disturbance projected to
approach southern Florida on Sunday, and its potential intensity
and track forecast. Models are in fairly good agreement that the
area of low pressure will move west-northwestward through the
Bahamas and toward the southern Florida peninsula around Sunday,
but diverge after that. On Monday, the GFS turns the disturbance
northward along the east coast of Florida, while the ECMWF takes
it across southern Florida before turning northward in the far
eastern Gulf, which would place it over Apalachee Bay on Tuesday
evening. Model intensity guidance is varied as well, with several
members keeping the disturbance as a tropical storm or weaker,
while others develop a stronger system. The eventual track and
intensity of this disturbance could result in significant changes
to our forecast early next week, so we will continue to closely
monitor this system.
.AVIATION [Through 18Z Thursday]...
The highest chance of TSRA this afternoon is in the FL Panhandle,
which will likely affect operations at KECP at times this afternoon,
with gusty winds and brief MVFR/IFR conditions. Elsewhere the
probability of TSRA is generally 20%, and the prevailing conditions
will be VFR. About 30% of the numerical guidance forecasts IFR Vis
at KVLD, KECP, and KDHN around dawn Thursday, which seems strange
given the expected influx of slightly drier air in the boundary
layer and non-zero wind speeds.
Easterly winds generally from 10 to 15 knots will result in 2 to 3
foot seas through Sunday, with a few locally higher waves
possible. Higher seas are possible early next week depending on
the eventual track of the tropical disturbance, but quite a bit of
uncertainty remains in its track and intensity at this time.
Drier air filtering in at upper levels will yield lower rain chances
and high dispersion values Thursday and Friday afternoons.
Otherwise, no fire weather concerns as RHs are expected to remain
above critical thresholds.
No flooding concerns are anticipated through the weekend.
Depending on the track of the tropical disturbance, heavy rain may
be possible next week over portions of our area. However, it is
too early to determine with much confidence where this could
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 73 95 72 95 71 / 10 10 0 10 0
Panama City 76 91 72 88 73 / 10 10 10 10 10
Dothan 73 94 70 94 70 / 10 0 0 10 0
Albany 72 95 69 94 67 / 0 0 0 0 0
Valdosta 71 94 71 94 70 / 0 10 0 10 0
Cross City 73 93 72 94 72 / 10 10 10 20 10
Apalachicola 77 90 76 89 76 / 20 10 10 10 10