Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 141520
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1120 AM EDT Thu Aug 14 2014
.Near Term [Through Today]...
Just made a few minor tweaks to the current fcst which is
essentially well on track. Both local and close proximity soundings
as well as the GOES Blended TPW (Total Precipitable Water)
product, show a tremendous gradient in the PWAT fields from NW to
SE across our CWA. As for the actual 12 UTC soundings, TAE`s came
in with 1.78" which is down from 2.28" from 12 UTC Wed., while FFC
is down to am extremely low 0.50", down from a still below climo
value of 1.19". Across just our CWA, using the TPW product
exclusively, as of 1250 UTC this morning, our lowest value was in
Quitman county GA (far NW) with 0.88" which is 54% of climo for
this time of year, while our highest values of 2.00" to 2.04" are
showing up across much of the SE FL Big Bend. So, our PoP gradient
of 10% to the NW to 70% is quite obvious. The only changes of
note to this package were to raise afternoon PoPs over the Marine
area, and High temps around Valdosta given the expected later
start to the convection.
.Prev Discussion [233 AM EDT]...
.Short Term [Tonight Through Saturday]...
The GFS and ECMWF forecast our region to remain north of a deep
layer ridge. A weakening, quasi-stationary front will remain
oriented east-northeast to west-southwest across our forecast area,
keeping the FL coast and north FL in the warm sector. Any cooler air
associated with this front will remain far north of our region, but
some slightly drier dewpoints (mid 60s) are expected in south GA &
AL. Although isolated, mainly afternoon & evening showers &
thunderstorms will develop near the front each day, dry, subsiding
air aloft will limit most of the deep moist convection to the
region south and east of Tallahassee. In fact, rain is possible at
almost any time of day (or night) around Cross City and Perry (as
well as over the northeast Gulf of Mexico) with persistent,
moist, onshore flow through Saturday. The PoP will range from 10%
at Dothan and Albany, to 40% at Cross City Friday and Saturday.
With drying and subsidence aloft, high temperatures will climb into
the mid 90s each day (except around 90 at the coast). The chances
for organized severe storms is low due to weak winds aloft.
.Long Term [Saturday Night Through Thursday]...
Deeper moisture should return on Sunday and into early next week
as southwest flow develops once again in the low-mid levels. From
Sunday to Wednesday, the forecast calls for scattered
thunderstorms, highs in the low-mid 90s and lows in the mid 70s.
[Through 06Z Friday] MVFR fog will be possible primarily at VLD
this morning. DHN, ABY, and most likely ECP will remain storm-free
and VFR today. There is a non-zero chance mid-afternoon for a
quick hitting storm at ECP so have included VCTS there. At TLH and
DHN expect MVFR to IFR conditions in thunderstorms later this
afternoon. All sites will return to prevailing VFR around sunset.
An east-west oriented high pressure ridge will remain situated
across South FL and the eastern Gulf of Mexico into early next
week. This will help to maintain west to southwest winds around
10 kt across the coastal waters, with 1 to 2 ft seas. Some
increase in onshore winds and chop is possible each afternoon &
evening with the heating of the land.
The Tri-State region will be bisected northeast to southwest over
the next few days by a front dividing dry air to the north and more
saturated conditions to the south. However, even in the driest
locations relative humidity levels should remain above critical
levels precluding any hazardous fire weather conditions.
Despite locally heavy rain the past few days, local Flash Flood
Guidance remains rather high- generally 3.5 to 5 inches (3 hr)
across north FL. The late-night run of our Ensemble Convection
Allowing Models (ECAM) indicates a less than 15% chance of
exceeding Flash Flood Guidance through Friday. However, with still
plenty of boundary layer moisture, rainfall rates could be locally
heavy and cause some flooding of in urban areas, low-lying spots,
or in small basins and streams. Area rivers were well below flood
stage, and this is likely to continue at least through this
.Preliminary Point Temps/PoPs...
Tallahassee 92 72 94 72 94 / 50 30 30 20 30
Panama City 88 76 90 76 90 / 30 10 20 10 20
Dothan 92 69 94 71 94 / 10 0 10 10 10
Albany 94 68 95 71 94 / 10 10 10 10 10
Valdosta 94 71 92 70 93 / 60 30 30 20 30
Cross City 88 73 91 72 90 / 70 40 40 30 40
Apalachicola 88 77 89 77 89 / 40 20 30 20 30