Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 020229
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
929 PM EST Sat Mar 1 2014
.Near Term [Through Tonight]...
Overnight, surface high pressure will settle over the region as an
upper ridge slides by aloft. The high pressure, coupled with dry
middle and upper layers of the atmosphere and a gradually
moistening boundary layer, will set the stage for some fog across
the region overnight. Best chance of widespread fog will be over
the eastern zones, directly under the center of the surface ridge.
At this time, with dewpoints still in the lower 40s, do not expect
significant dense fog, so have dropped that wording from the
forecast. Otherwise, forecast is on track, with low temperatures
in the mid 40s expected across the forecast area.
[Through 00Z Monday]...VFR is expected everywhere until around
09z. The HRRR and local hi-res guidance show IFR-LIFR conditions
developing overnight along the coast at ECP and from the east at
VLD, with MVFR conditions possible tonight at TLH and ABY.
Conditions should begin to improve to VFR after daybreak and
remain VFR for the rest of the period. Calm to light winds will
become SSW at less than 10 knots.
.Prev Discussion [304 PM EST]...
.Short Term [Sunday Through Monday Night]...
Deep layer ridging will hold through Sunday, providing us with
another dry afternoon. The only difference is that tomorrow should
be several degrees warmer than this afternoon. Away from the
coast, expect most locations to climb into the middle and upper
70s, with near 80 degrees expected across the southeast Big Bend
of Florida. Nearer to the coast, expect a slightly cooler
afternoon, with temps peaking in the upper 60s.
Sunday night through Monday, a shortwave trough will move through
the Southeast, dragging a cold front through the area on Monday.
The associated surface low and weak LLJ will be pulling out of the
local area through the day, thereby weakening the low-level
convergence and wind field. Additionally, the ECMWF and NAM are in
rather decent agreement that mid-level dry air will quickly
overspread the Tri-State area as the front is progressing through,
effectively capping any deep, moist convection. Thus, severe
weather is not anticipated at this time. Further, the intensity
and coverage of rain should also wane through the day. Therefore,
expect average rainfall amounts to be near a half of an inch west
of the Apalachicola and Chattahoochee Rivers, and generally
remaining below a quarter of an inch elsewhere.
Expect a decent temperature gradient both Monday and Monday night
across the region. High will range from near 80 degrees across the
southeast Big Bend, to the mid 60s across southeast Alabama.
Overnight, a solid push of CAA will drop temperatures into the mid
30s across Alabama, while lows will hover near 50 degrees to the
southeast in the immediate wake of the front.
.Long Term [Tuesday Through Saturday]...
The main concern in the extended period comes on Thursday as a
potent shortwave carves through the northern Gulf, resulting in
rather significant Gulf cyclogenesis. This forecast will favor the
12z ECMWF as it has held a much steadier forecast over the past
couple of days, and is also supported by the CMC. The surface low-
track, as well as the low and deep layer wind profiles are quite
concerning with respected to severe convection. Both the ECMWF and
the CMC, depict a 50+ KT LLJ nosing right up Apalachee Bay.
Further, a strong mid-level jet max raises deep layer shear values
over 60 knots. However, as impressive as that is, both the ECMWF
and CMC depict enough isentropic rain ahead of the dynamic system,
to effectively cut off any chance of surface based storms.
Nonetheless, with considerable differences between the GFS and
ECMWF, the forecast remains highly uncertain and with such
impressive wind fields, all interests should pay close attention
to forecast changes as the system draws nearer.
Low winds and seas will continue until Monday when a cold front
crosses our Gulf waters increasing winds to cautionary levels.
Winds and seas will once again subside through mid-week, until an
area of low pressure may bring a substantial increase late next
Minimum inland RH this afternoon will drop to around 30 percent with
ERC and 20 foot winds also below critical levels. The airmass will
begin to moisten up on Sunday and more so on Monday associated with
the next cold frontal passage. Expect elevated transport winds and
dispersions on Monday mainly for the inland Big Bend and adjacent
GA counties. In the wake of the front...the airmass will modestly
dry out but rain chances again increase Wednesday through Thursday
Eve. Red flag levels are not expected through the upcoming work
The Apalachicola River at Blountstown will drop below flood early
this evening. Otherwise there are no concerns on area rivers through
the early part of next week.
.Preliminary Point Temps/PoPs...
Tallahassee 44 76 50 75 42 / 0 0 0 30 20
Panama City 50 65 59 66 42 / 0 0 10 40 20
Dothan 45 77 56 68 36 / 0 0 10 70 10
Albany 45 77 55 70 40 / 0 0 0 40 20
Valdosta 46 77 50 76 43 / 0 0 0 40 30
Cross City 45 78 49 77 50 / 0 0 0 20 20
Apalachicola 49 65 59 69 45 / 0 0 0 30 20