Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 060531
Area Forecast Discussion
National Weather Service Tallahassee FL
1231 AM EST Tue Dec 6 2016
.AVIATION [Through 06Z Wednesday]...
Degraded flight conds the next 6 to 12 hours as IFR/LIFR
conditions continue with waves of showers and thunderstorms moving
through the tri-state region. Conditions will improve from west to
east mid morning through early afternoon as a cold front sweeps
through and takes the rain and low cigs with it. A return to VFR
is expected in the afternoon hours but MVFR conds look to return
after 00z at all terminals with high low level moisture in place.
.PREV DISCUSSION [1031 PM EST]...
.NEAR TERM [Through Tonight]...
The 7 pm EST regional surface analysis showed a well-defined,
quasi-stationary front along the FL-GA border, through Destin, and
westward to a triple point near the LA coast. Numerous showers and
thunderstorms were across our forecast area, some with very heavy
rain, and even a few with decent low-level meso cyclones. Vapor
imagery and upper air data showed a potent short wave trough
lifting northeastward over the LA-TX border.
The aforementioned surface front bulged unexpectedly northward
into extreme south GA this evening, while a "wedge" of relatively
cool, stable air was still across the FL Panhandle and southeast
AL. This should limit the threat of surface-based severe storms to
the region along and south of a line from Destin to Valdosta (i.e.
along the front). Both the 0-1 km and 0-6 km bulk shear
magnitudes support storm organization, with isolated bowing
segments (damaging wind gusts) and supercells (tornadoes)
possible. Additionally, due to unusually high surface dewpoints
and temperatures, MLCAPE values will be in the 500-1000 J/KG
range, which is quite high for the cool season.
Eventually the strengthening low-layer winds associated with the
approaching mid layer short wave trough will push the front
northward, enough so that the severe threat will cover most of our
forecast area. There is good agreement among the latest NWP
guidance in bringing a ragged band of storms through our region,
from west to east, late tonight through Tuesday morning. The
weather will improve quickly behind this rain band.
.SHORT TERM [Tuesday Through Wednesday Night]...
The mid-upper level shortwave driving our disturbed pattern will
eject across the Tennessee valley and into the mid-Atlantic
Tuesday, with the surface cold front quickly sweeping west to east
through our area Tuesday morning. Models show 0-1 km shear of
30-35 kts and 0-6 km shear of 40-50 kts across the area, with a
tongue of 600-1000 J/kg SBCAPE over the FL Big Bend and into SW
GA. Strong to severe storms will remain possible Tuesday morning
ahead of and along the cold front, with the main potential hazards
being damaging winds and isolated tornadoes.
Tuesday night through Wednesday night we`ll be in a more quiet
pattern characterized by a broad long wave trough covering most of
the CONUS and weak low level ridging over the southeast. Morning
lows will be in the upper 40s to low 50s and highs Wednesday will be
in the mid 60s to around 70.
.LONG TERM [Thursday Through Monday]...
As a weak shortwave swings through the broad UL trough, a weak (in
terms of energy/forcing), mostly dry cold front will develop and
quickly push through the area Thursday and Thursday night. PoPs are
around 20% as this system passes. Behind it, however, a much colder,
drier air mass will move in and bring us some of the coldest
temperatures for the season so far. Lows Friday morning will be in
the 30s and will likely dip into the upper 20s in our northern zones
Saturday morning. Highs will only be in the upper 40s to low 50s on
Friday. As high pressure moves into place over the weekend, we will
warm up again with highs returning to the mid 60s-low 70s early next
Stormy seas tonight and tomorrow with winds around 20 knots and seas
of 6-7 feet over our western waters and cautionary conditions over
our eastern waters. Winds and seas will lower Tuesday night, but
will ramp back up Thursday night through Friday with our next
A moist airmass with periodic rainfall will mitigate fire weather
concerns over the next several days.
Over the past 24 hours much of the area saw 1 to 3 inches of rain
with up to 5 inches in parts of southeast Alabama. Additional
rainfall amounts range from around 1 inch in the Big Bend to 3
inches near Albany and Dothan. This has caused a rise on area
rivers, however, the only one forecast to approach flood stage is
the Shoal River.
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 77 52 71 48 67 / 60 0 0 0 20
Panama City 72 54 66 53 63 / 40 0 0 0 20
Dothan 72 50 66 47 59 / 50 0 0 0 20
Albany 76 50 67 47 62 / 70 0 0 0 20
Valdosta 77 51 70 47 66 / 70 0 0 0 10
Cross City 77 51 71 48 69 / 70 0 0 0 20
Apalachicola 74 54 67 53 67 / 50 0 0 0 20
GM...Small Craft Advisory until 7 PM EST this evening for Coastal
waters from Apalachicola to Destin FL out 20 NM-Waters from
Apalachicola to Destin FL from 20 to 60 NM.