Near Term [Through Tonight]...
The Arctic front can be easily identified this afternoon, stretching from southeast Texas up through central Alabama and northeastward from there.
The front will continue moving southeastward and move through our area tonight.
Areas of showers will continue ahead of the front and affect the region through the evening hours.
Behind the front, cold air will advect into the area, but through sunrise, it appears as though precipitation will hold off in the sub-freezing air.
However, things will change during the day on Tuesday in portions of the forecast area, and that is discussed below.
Short Term [Tuesday Through Wednesday Night]...
Finally the global models have come into much better agreement,
especially with their handling of the southern stream trough currently over Baja Peninsula.
The GFS has joined the ECMWF camp in not quite phasing this system with the main short wave trough (currently over the upper Plains).
This essentially means a shorter duration of precipitation than was being forecast by earlier NAM/SREF/GFS runs.
This will result in lower QPF amounts than what that camp of guidance had originally forecast (which would have been historic).
The global models have also trended toward an initially shallower arctic airmass, which would lessen the threat for snow accumulation farther south as any transition to sleet/snow would occur about the time the precipitation tapers off.
However, some enhanced frontogenesis aloft may cause a quick
"burst" of snow/sleet in our northwest zones, totaling 1 to 2 inches in a 3-hour period.
Even places as far south as Tallahassee, Valdosta, and Panama City will likely get a period of light freezing rain late Tuesday night and/or Wednesday Morning.
It appears less likely that there will be measurable snow in this
area, though trace amounts are possible Wednesday morning or early afternoon- just before the precipitation ends.
The temperature forecast is a bit tricky because of competing factors (latent heating, evaporative cooling, strong cold/dry air advection, etc.), and in this case we leaned more toward the raw model output, which is often more realistic than the normally favored MOS.
This means that temperatures could be near freezing in portions of South AL and GA Tuesday afternoon, resulting in freezing rain a little earlier than previously thought.
Lows Wednesday morning will range from the mid 20s north of Dothan and Albany, to mid 30s south of Interstate-10.
Highs on Wednesday will only be in the 30s, and we may meet Wind Chill Advisory levels across portions of the forecast area Tuesday night and Wednesday.
Although our forecast snow and ice amounts are mostly below our
local criteria for a Winter Storm Warning, we have decided to go with a warning to avoid confusion (between neighboring WFOs and from our previously worded watch).
It`s also possible that isolated amounts (either ice or snow) may exceed our local warning criteria.
The main impact appears to be hazardous travel, but if there as heavier icing than forecast, power outages could become a problem.
This would make people in non-winterized shelters (and without true winter clothing) vulnerable to a prolonged period of cold temperatures and low wind chills.
Long Term [Thursday Through Monday]...
The GFS and ECMWF were in good agreement as their forecast 500 mb height patterns gradually transition from a fairly zonal one early
in the period, to that of a more amplified (but still progressive)
one by the weekend.
After a possible light freeze Friday morning, our forecast area will undergo a warming trend.
Highs will be in the 60s Friday, then 70s for the weekend and early next week.
Lows will be in the 40s Saturday, then 50s Sunday and Monday.
A weak frontal system will increase PoPs into the 20-30% range
Sunday and Monday.
A band of showers continues to move eastward across our region.
MVFR/IFR conditions will be possible at all terminals even after the showers move off to the east, with low ceilings and/or patchy fog lingering at all terminals overnight into the early morning Tuesday.
Areas of rain are expected to move back into our region between 12Z-18Z Tuesday and continue through the rest of the period.
Northerly winds will remain around 10 kt at all terminals, and there is a chance that freezing rain could develop at DHN late Tuesday afternoon into the evening.
Model data indicates that dense sea fog will develop overnight and
we have issued a dense fog advisory for the waters east of
Any fog that develops will be swept away with the passage of an Arctic cold front.
Advisory conditions are expected west of Apalachicola tonight and then gradually expanding east on Tuesday night into Wednesday.
A decrease in winds and seas is expected for the end of the week.
Drier air will arrive behind a cold front by Wednesday.
However, the air will be too cold to achieve critical relative humidity
levels and therefore red flag criteria are not expected to be met
A moistening trend is forecast beginning on Friday.
No significant hydrology concerns are expected through the next
Preliminary Point Temps/PoPs...
Tallahassee 44 44 32 36 27 / 60 60 80 50 10
Panama City 43 43 32 38 30 / 60 70 80 40 10
Dothan 34 35 26 33 21 / 50 70 80 20 10
Albany 37 38 28 34 21 / 60 70 80 30 10
Valdosta 45 45 31 36 28 / 50 60 80 50 10
Cross City 56 57 36 39 34 / 30 50 70 50 20
Apalachicola 49 49 36 39 32 / 60 60 70 50 10
Winter Storm Warning from 1 PM EST /Noon CST/ Tuesday to 1 PM
EST /Noon CST/ Wednesday for Calhoun-Central Walton-Coastal Bay-Coastal Franklin-Coastal Gulf-Coastal Jefferson-Coastal
Wakulla-Gadsden-Holmes-Inland Bay-Inland Franklin-Inland Gulf-Inland Jefferson-Inland Wakulla-Inland Walton-Jackson- Leon-Liberty-Madison-South Walton-Washington.
Winter Storm Warning from 1 PM Tuesday to 1 PM EST Wednesday for Baker-Ben Hill-Berrien-Brooks-Calhoun-Clay-Colquitt-Cook-
Winter Storm Warning from Noon Tuesday to Noon CST Wednesday for Coffee-Dale-Geneva-Henry-Houston.
Small Craft Advisory from Midnight tonight to 11 AM EST Tuesday for Coastal waters from Apalachicola to Destin FL out 20 NM-Waters from Apalachicola to Destin FL from 20 to 60 NM.