Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 201503
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1003 AM EST Fri Feb 20 2015
.Near Term [Through Today]...
We broke record low temperatures this morning at Tallahassee and
Apalachicola. Temperatures dropped to 22 at Tallahassee this
morning, breaking our previous record low of 27 set in 1993. At
Apalachicola, it got down to 30, breaking the previous record of 32
set in 1977. Fortunately, the arctic air mass in place will begin to
exit the area today. As surface high pressure moves off the Atlantic
coastline, we will begin to see winds from the east and then
southeast, returning moisture and warmth to the area. Skies will be
mostly clear today, although isentropic lift to our northwest will
mean increasing cloud cover through the period, particularly in our
northwestern zones. Highs will warm to the upper 40s to mid 50s
[Through 12Z Saturday] VFR conditions will prevail through the
period with light winds.
.Prev Discussion [333 AM EST]...
.Short Term [Tonight Through Sunday]...
Over the course of the short range forecast, the anomalous eastern
CONUS trough will lift out of the Southeast with mostly zonal flow
prevailing aloft as the southern stream lifts north. By Sunday, a
northern and southern stream anomaly will merge over the Southern
Plains and move east into the Mississippi and Ohio Valleys. At the
surface, high pressure will follow behind the departing trough,
veering flow to the south Saturday through Sunday. Through the day
Sunday, a cold front will near the Tri-State region associated
with the aforementioned merging systems.
As far as rain chances are concerned, we`ll remain mostly dry
through Sunday. Saturday features no chance for rain, while a
slight chance exits on Sunday as weak isentropic ascent may occur
with the veering low-layer flow and some rain may creep into our
westernmost counties associated with the approaching frontal
system. So, the best chance for rain on Sunday will be west of the
Apalachicola river in Florida, and across southeast AL and extreme
A drastic change in temperatures is expected during the period.
Both Saturday and Sunday will feature above average daytime
temperatures, with highs in the low 70s on Saturday, and possibly
in the middle to upper 70s on Sunday. While we`ll have one more
night in the 30s tonight, Saturday night will likely be in the 50s
.Long Term [Sunday Night Through Friday]...
There is a lot of uncertainty in the extended range forecast as
the GFS and ECMWF cannot agree on the strength of a northern
stream anomaly diving through the Plains. Thus, this difference
propagates into just how the northern stream will affect the
southern stream, and subsequently how the surface patterns evolve
locally. Either way, it appears as though we`ll be transitioning
over to a wet period with the possibility for two frontal systems,
one early next week, and another later in the week. With a more
active pattern, expect average temperatures to be slightly below
normal, though the coldest air would likely be behind the second
system late in the week.
Winds will gradually increase through today, eventually to
advisory levels tonight as the calm center of high pressure moves
east. Expect headline conditions to cease as a weak area of low
pressure moves through the Gulf late in the weekend. We`ll likely
see a couple rounds of headline levels next week as a couple of
frontal systems move into and through the Gulf.
The dry airmass will continue to encompass the region today. Red
flag warnings continue for Southeast Alabama and Walton County
Florida and have now also been issued for Leon and Wakulla Counties
in Florida. ERC values were observed very near criteria in the
latter two counties yesterday and another very dry afternoon with RH
down in the teens is expected to bump this fuel moisture component
to critical levels today. Onshore flow will increase humidity levels
substantially for Saturday with red flag conditions not expected
next week. Dispersion indices will be relatively low today and high
Rivers are currently running low. While rain chances will return
over the weekend, rainfall totals are not expected to be sufficient
to cause any flooding concerns.
.Preliminary Point Temps/PoPs...
Tallahassee 54 36 70 51 77 / 0 0 0 10 30
Panama City 52 45 66 58 70 / 0 0 0 20 40
Dothan 49 36 68 52 72 / 0 0 0 30 50
Albany 48 33 67 50 73 / 0 0 0 20 40
Valdosta 50 34 69 50 77 / 0 0 0 10 20
Cross City 53 35 71 51 78 / 0 0 0 10 10
Apalachicola 53 45 65 58 70 / 0 0 0 10 30
FL...Red Flag Warning until 5 PM CST this afternoon for Central
Walton-Inland Walton-South Walton.
Red Flag Warning until 7 PM EST this evening for Inland Wakulla-
AL...Red Flag Warning until 5 PM CST this afternoon for Coffee-Dale-
GM...Small Craft Advisory from 7 PM this evening to 7 PM EST Saturday
for Coastal waters From Ochlockonee River to Apalachicola
FL out to 20 NM-Coastal waters from Apalachicola to Destin
FL out 20 NM-Waters from Suwannee River to Apalachicola FL
from 20 to 60 NM-Waters from Apalachicola to Destin FL from
20 to 60 NM.