Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 031639
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1139 AM EST Tue Mar 3 2015
.Near Term [Through Today]...
Current fcst is at least on track if not a bit ahead of schedule
with almost all of the remaining fog and low clouds over the
interior now either dissipated or confined to the coastline of the
western FL Panhandle or NW portions of SE AL and Quitman county in
GA. In the very expansive area of sunshine, temps are already
pushing into the mid to upper 70s over much of the interior, well
on their way to the lower or possibly even middle 80s. Did reduce
PoPs from 30 percent to 20 percent across northern portions of the
CWA, but this was a very minor change over a fairly small area.
Over the Coastal Waters, with about 90 percent of the marine area
to the east of Apalachicola now cleared out from the fog and low
clouds, was able to cancel the Marine Dense Fog Advisory for the
four eastern zones. Due to the cool shelf waters, however, realize
that this may be a temporary condition.
.Prev Discussion [444 AM EST]...
.Short Term [Tonight Through Thursday]...
For tonight, we should see additional widespread fog, as has been
the case the past couple nights. However, the fog near the coast
and in the western part of our area may be forced more by
advection processes than radiational cooling - as has been the
case previously. This will be due to increasing southerly flow
over the cooler shelf waters near the coast and in Apalachee Bay.
The end result will be roughly the same, and we will likely have
to contend with some dense fog again.
The primary forecast concern on Wednesday will be related to high
temperatures, as QC forcing associated with an approaching cold
front will still largely be situated to our northwest. The
greatest uncertainty exists within 20 miles of the coast and in
the western third of the area, where SREF probabilistic guidance
and several deterministic models maintain BKN-OVC skies for much
of the day. With persistent southerly winds all day, it would not
be too surprising to see stratus and/or fog lingering most of the
day near the coast. Meanwhile, inland in the Big Bend and SW
Georgia, clouds and fog seem more likely to scatter out. In these
areas, guidance puts highs near 80 degrees, and this seems
reasonable given similar boundary layer temperature profiles to
yesterday when highs were near 80 in sunnier locations. Closer to
the coast and in SE Alabama and the western FL Panhandle, we kept
highs in the low-mid 70s, although if OVC skies or fog linger all
day, that could still be a bit too high.
A relatively shallow cold front will approach on Wednesday Night
and push through the area on Thursday. This will bring rain
chances north and west by Wednesday Night and into the rest of the
area on Thursday. The strongest QG forcing will be well to our
north closer to stronger mid-level PVA, which should lead to
scattered, light showers in our area. Some models show enough
marginal instability for a few storms, so that was also included.
High temperatures in the western half of our area will likely be
achieved early in the day, with falling temperatures thereafter.
.Long Term [Thursday Night Through Tuesday]...
As the surface front passes south of our area, it will begin to
stall given a stagnant upper level pattern. The cold front will be
sloped back to the northwest in the vertical, intersecting the
850mb surface roughly near our area. As a few weak waves aloft
eject along the Gulf coast, and the region remains in the right
entrance region of an upper level jet, some rain showers will be
possible into the weekend to the north of the stalling surface
front. Rain chances are low (20-30%) but cloud cover should keep
high temperatures below normal.
[Through 12z Wednesday] Widespread IFR/LIFR ceilings and
visibilities due to fog at least through daybreak. All terminals
should become VFR by this afternoon only to experience similar
conditions overnight tonight into Wednesday morning. Winds will be
light from the southeast to south.
The main weather story for our marine zones over the next 48 hours
will be fog, and it is very likely to be dense in spots through
much of the period - particularly over Apalachee Bay. The latest
tower and buoy observations confirm 0-1F dewpoint depressions,
with coastal observations reporting visibility under 1 mile (to
around 1/4 mile at times). Combined with satellite information,
this suggests that fog and stratus are lingering over much of the
marine forecast area, and models show that continuing through the
day. Therefore, the Marine Dense Fog Advisory is continued through
7 PM EST, and it may need to be further extended. A cold front
will arrive on Thursday, bringing advisory level winds in its wake.
Red flag conditions are not expected for the next several days.
The Ochlockonee River at Havana is forecast to reach minor flood
stage overnight and will crest on Wednesday. The Apalachicola at
Blountstown, Withlacoochee at Valdosta and Ochlockonee at Concord
have all crested and will fall below flood stage by tomorrow
.Preliminary Point Temps/PoPs...
Tallahassee 81 59 81 64 69 / 10 10 10 30 50
Panama City 74 60 71 63 66 / 10 10 20 40 50
Dothan 81 60 77 60 61 / 20 10 30 50 60
Albany 80 59 80 62 65 / 20 10 20 40 60
Valdosta 83 61 83 63 73 / 20 10 10 20 50
Cross City 82 60 83 61 75 / 10 10 10 10 40
Apalachicola 73 60 68 63 68 / 10 10 10 30 40
GM...Dense Fog 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.