Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 020236
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
936 PM EST Sun Mar 1 2015
.Near Term [Through Tonight]...
The Tri-State region remains in the stubborn zonal flow regime
aloft, with a cool wedge of high pressure at the surface.
Although there will still be some drizzle around tonight, the
threat for light rain is much less than previous nights as the
coolest core of the wedge has retreated north a bit. This is
evident in this evenings 00z sounding where the temperature
difference between the bottom and the top of the inversion is only
about 4 degrees, as opposed to around 10 degrees this time
yesterday. Additionally, the depth of the cool layer has shallowed
about 1kft from yesterday. Essentially all this means is that
isentropic surfaces will be sloped less and over a narrower
vertical window, resulting in very weak (if any) low level
isentropic ascent. The best chance for any light rain tonight will
be across southeast Alabama and parts of the far western Florida
panhandle. Rain generated along a stationary front in the
Mississippi Valley will drift east into these areas tonight, though
with low layer flow veering westerly and a rather uniform zonal
temperature gradient, expect rain to be on a weakening trend.
The weakening winds will also increase the chances for widespread
fog overnight, which is already occurring in most locations. The
question becomes just how dense will the fog become. If the winds
are able to go completely calm tonight, expect that the fog will
become quite dense. There are also some signals that sea fog may
begin to develop off the west coast of the Peninsula as high
dewpoint air moves over the cool northeast Gulf shelf waters in
the veering flow. The tricky part will be the timing of this
advection as it will need to occur before sunrise when the near
surface air will begin to warm. Should the fog develop tonight, it
will likely stay socked in all day tomorrow, gradually spreading
west through the Gulf.
[Through 00Z Tuesday]...
IFR ceilings will fall into the LIFR category at all terminals
tonight. There is much lower confidence as to just how dense fog
will get, however expect at least MVFR visibilities at all
terminals with the potential to fall to LIFR. Ceilings will likely
not scatter out tomorrow, and only lift into the MVFR window once
.Prev Discussion [314 PM EST]...
.Short Term [Monday Through Tuesday Night]...
It continues to be a challenging day time temperature forecast
with the model guidance showing the cold wedge hanging on through
at least 15 UTC. Given the models relatively poor performance with
Sunday`s temperatures, prefer to follow more of a persistence
approach in keeping the wedge around until at least late afternoon
when it seems to make sense that enough mixing could then take
place - along with surface winds picking up more of a southerly
component. With this in mind, Southwestern Georgia would likely be
the last place to see warmer temperatures, so have departures from
guidance as high as 10 degrees in portions of the area on Monday.
Essentially, this has highs in the lower 60s for our northern
zones to as warm as the upper 70s in the Southeast Florida Big
Bend. Obviously, should the cold wedge and cloud cover scatter out
quicker than predicted, warmer high temperatures would occur.
By Tuesday, a building mid level ridge and a warm front lifting
north into the Tennessee Valley will erode whatever cool air is
left, and deliver a warm, but mostly cloudy day across the region
with highs in the mid to upper 70s. Only light showers are
expected across the northern portion of the area near to the
surface warm front.
.Long Term [Wednesday Through Sunday]...
Continued warm weather will start the extended period with
southerly flow in place for Wednesday. High temperatures may end
up approaching 80 degrees in some spots.
By Thursday, a cold front will move through the area, bringing a
chance of light rain and much cooler air. Though rainfall amounts
will be light, guidance this cycle indicates this frontal zone
stalling across the forecast area through much of the weekend,
yielding cool and unsettled conditions. There is some disagreement
on whether a southern stream impulse late in the weekend will
interact with this boundary bringing a round of heavy rain to the
area by Sunday night. For now, will show 30 percent PoPs that far
out given limited model agreement in this scenario. Temperatures
from Thursday through Sunday will be well below normal for
afternoon highs and just a couple degrees below normal for
Winds will continue to decrease across the marine area this
evening and remain low through Tuesday. By Wednesday, southerly
flow will increase ahead of an approaching frontal boundary. This
front will move through the area on Thursday, shifting to winds to
offshore and increasing to advisory levels through Friday.
Hazardous fire weather conditions are not expected over the next
several days. However, due to a combination of low transport winds
and mixing heights, dispersion indices will remain quite low on
Monday. More typical dispersion indices will return on Tuesday.
Area streamflows remain above normal. The Ochlockonee and
Withlacoochee Rivers are now in action stage at each of the
forecast points. Minor flooding is possible for the Withlacoochee
River at Valdosta late this evening.
No significant rainfall is expected for the next few days, so no
additional river flooding is anticipated at this time.
.Preliminary Point Temps/PoPs...
Tallahassee 54 70 59 75 58 / 10 10 10 10 10
Panama City 57 68 59 69 61 / 10 10 10 10 10
Dothan 50 67 58 76 61 / 30 10 20 10 10
Albany 48 61 57 76 59 / 20 10 30 10 10
Valdosta 53 69 59 78 60 / 10 10 20 10 10
Cross City 60 77 58 77 60 / 10 10 10 10 10
Apalachicola 57 67 60 68 62 / 10 10 10 10 10