Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 080246
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
946 PM EST Sat Dec 7 2013
...Dense fog possible across Apalachee Bay and the Florida Big
.NEAR TERM [Tonight]...
Across the CONUS, the upper levels are dominated by a large trough
with a small elongated ridge over central and southern Florida.
There appears to be a remnant upper level PV anomaly that
essentially stretches from west to east across the local area,
though it is likely too weak too impact the surface weather
Our sensible weather has been primarily associated with a
surface front stretching from Apalachicola northeast through
Tifton as of 02z. There were also a few showers across southeast
Alabama and southwest Georgia earlier this evening associated with
the far reaches of a week lee trough/low-level PV anomaly.
Comparing a 21z and 01z subjective surface analysis, there has
been zero movement of any of the aforementioned surface features.
Although there were some earlier indications that the northern
extension of the front would return south as a backdoor front and
reach our northern Georgia counties, the latest hi-res model suite
tends to agree with the hand analysis and would suggest there will
be almost no movement to the entire frontal system overnight. This
also means that winds will be slower to veer southeasterly through
the night and should limit any weakly forced isentropic showers.
So, the main forecast challenge becomes discerning where dense fog
formation will occur tonight. Winds will be calmest out ahead and
away from the front over land and should remain light out of the
east across Apalachee Bay. Thus, expect a large area of dense
radiationally induced fog across the interior Florida Big Bend.
Closer to the coast, mid 60 dewpoints will advect into the Gulf
where the near surface air will cool to around that number due to
the cool shelf waters. This will likely induce some advection
(sea) fog across Apalachee Bay that will likely move west and
affect the Forgotten Coast overnight.
Expect near a 10 degree temperature difference between southeast
Alabama and the southeast Big Bend of Florida; with mid 50s to the
northwest, and mid 60s southeast.
.SHORT TERM [Sunday Through Monday Night]...
As shortwave impulses continue to propagate through the mid and
upper level trof over eastern Canada, we will stay under the right
entrance region of the mid and upper level jets. The lack of
eastward progression of the jet will help stall out the surface
cold front tonight and eventually help it retrograde back to the
northwest tomorrow. This will mean continued unseasonably warm
temperatures, heavy cloud cover, foggy mornings, and higher
chances of rain in our southeastern Alabama counties than
elsewhere. Highs will be in the upper 70s and low 80s and lows
will be in the upper 50s to low 60s with the coolest temperatures
in southeast Alabama.
.LONG TERM [Tuesday through Saturday]...
We should finally start to see a break in the disturbed pattern
beginning in the long term as the upper level trof finally makes some
eastward progress and pushes the front across our area Tuesday
through Tuesday night. Higher pressure will build eastward behind
it, allowing us to get some cooler air. Highs will be in the upper
50s to mid 60s and lows will generally be in the 40s after the
frontal passage. The GFS is suggesting that later next week, a warm
front may move inland from the Gulf, giving us about a 30% chance of
rain once again heading into the weekend.
.AVIATION [Beginning 02Z Sunday]...
Low cigs will maintain MVFR and IFR/LIFR conditions through much
of the forecast period as a cold front meanders and then stalls
just east of the area. Areas of fog can once again be expected 00Z
Mon with MVFR CIGS/VSBYS dropping to IFR after 07z and then at
least brief LIFR in widespread dense fog towards sunrise into
morning hours especially at TLH and VLD south of cold front. Dont
expect MVFR CIGS/VSBYS there until late mornnig and VFR until
The cold front that moved into the coastal waters today has stalled
this evening. Dense fog will be possible throughout Apalachee Bay
overnight. Winds should generally remain below 15 knots with
scattered light showers possible through Monday. Winds will shift
to south to southeast before the arrival of the next cold front
Tuesday. The second cold front will likely bring at least
cautionary winds of 15 to 20 knots, and possibly some advisory
conditions, especially offshore.
Fire weather concerns will remain minimal with high RH and
abundant moisture around.
Generally light rainfall amounts will have little impact on area
rivers through the forecast period.
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 61 79 60 78 63 / 50 10 20 20 30
Panama City 60 75 65 76 64 / 20 10 20 30 30
Dothan 54 74 63 77 59 / 30 30 30 40 50
Albany 56 76 61 78 61 / 30 30 30 40 40
Valdosta 62 79 61 80 63 / 50 10 20 20 30
Cross City 64 81 59 80 63 / 20 10 20 10 20
Apalachicola 64 73 64 74 66 / 30 10 20 20 30
FL...Dense Fog Advisory until 10 AM EST Sunday for the Big Bend.
GM...Dense Fog Advisory until 10 AM EST Sunday for coastal waters
from Apalachicola to the Suwannee River out 20 NM.