NEAR TERM [Through Tonight]...
The long wave pattern is a familiar one today with a sharp ridge along the west coast and a broad trough dominating much of the rest of North America.
The next in a seemingly unending series of short waves is diving southeastward across the Northern Plains this afternoon and will reach the Ohio Valley by 12z.
This system will bring yet another cold front to our doorstep by sunrise.
The cold air will not have time to arrive overnight, so we will actually see min temps at or just above seasonal levels.
The trickier part of the forecast is the precip chances.
Several of the global and hi-res models are showing showers developing along and just ahead of the front as it approaches the coast.
We have included isolated showers for the FL Panhandle with any thunderstorms remaining offshore through 12z.
SHORT TERM [Tuesday Through Wednesday Night]...
The aforementioned cold front should sweep through the forecast
area in the morning hours Tuesday.
Moderately strong QG forcing and mid-level height falls should be offset by a relatively dry air mass in terms of precipitation production.
The result should be mainly isolated-scattered showers over the southern half of the area, especially 12-18z.
Consensus PoPs are in the 20-40% range and the forecast closely reflects this - with a dry forecast across the far north near DHN and ABY.
There is sufficient instability in enough model forecast soundings to warrant the inclusion of some isolated thunderstorms, mainly over the Gulf and in coastal areas.
The surface low over the Carolinas during the day, and the low-level wind field (925-850mb) over our area, should be about 2 standard deviations stronger than normal.
This suggests a synoptic pattern that should be favorable for a breezy day.
Forecast winds (around 20 mph) and wind gusts (as high as 35 mph) currently fall short of Wind Advisory criteria.
Based on this and collaboration with WFOs in MOB and JAX, we will hold off on a wind advisory for now, but it will certainly be a breezy day.
We went with a non- diurnal trend with temperatures falling generally after 16-18z.
We should see two consecutive nights with highs in the mid to upper 20s on Tuesday Night and Wednesday Night.
The situation on Tuesday Night should be an advection freeze, with our area remaining firmly in the surface pressure gradient and the surface high off to the NW.
Four of the top five CIPS analogs had lows in the mid-upper 20s, and model guidance was very consistent - increasing confidence in the forecast.
These temperatures should be accompanied by 5-10 knots of wind, which means most of our area will see wind chills near or just below Wind Chill Advisory criteria. An advisory could become necessary by the overnight shift for parts of the area.
Winds will be much lower on Wednesday Night as the high becomes situated over the area.
On both nights, our current forecast has us just avoiding hard freezes.
As is typical with a shallow cold air mass, this also sets up a chilly Wednesday by Gulf coast standards with highs in the 40s. We used a blend of raw model guidance and MOS.
We also kept morning temps a bit cooler, as the morning hours usually see a much slower warming trend than normal with suppressed mixing.
LONG TERM [Thursday Through Monday]...
Another cold front on Thursday will bring a reinforcing shot of cold air and set up a continued run of below normal temperatures into the weekend.
Some hard freezes are possible in this time frame, so agricultural interests should stay tuned.
For now, it looks like we should avoid any teens, and with temperatures above 20 degrees the main concerns for impacts on the cold nights would be with crops or plants.
The global models show a variety of trends for a weak Gulf low later in the weekend or possibly into Monday.
This could spread some light rain into the area, but the details are very uncertain given model inconsistencies.
VFR conditions under mostly clear skies and light southwest winds are expected until the pre-dawn hours Tuesday.
Some guidance suggests MVFR ceilings or visibilities could develop
We included this for a few terminals and hinted at it at others.
We could see an isolated thunderstorm near the coast just ahead of a strong cold front and we included this mention for ECP only.
Gusty northwest winds are expected behind the front.
Wind gusts could approach 30 knots at DHN and will generally be 20+ knots elsewhere.
We opted to issue a Small Craft Advisory - starting at 12z tomorrow
west of AAF, and 16z east of AAF - as winds should increase quickly behind a cold front on Tuesday morning.
Sustained NW winds should reach 20-25 knots with gusts to 30 knots.
A brief lull on Wednesday and into Thursday morning will be followed by another cold front and increase in winds late on Thursday.
Relative humidity values will remain above critical levels through
In the wake of a cold front, transport winds will be quite high on Tuesday resulting in high dispersion indices.
On Wednesday, significantly drier air will be in place and warning decisions will be based on fuel moisture levels for FL.
At this time, we do not think they will be dry enough to achieve criteria.
In AL and GA, it will not be windy enough to reach their respective criteria.
The rest of the week will remain dry, although Wednesday will be the
Area creeks and rivers are steady or falling.
A few area rivers are in action stage, but are not forecast to reach flood stage.
No significant rainfall is expected through the forecast period.
Preliminary Point Temps/PoPs...
Tallahassee 42 61 28 48 26 / 10 20 0 0 0
Panama City 51 61 31 48 35 / 20 20 0 0 0
Dothan 41 56 27 47 29 / 10 10 0 0 0
Albany 39 58 26 46 26 / 10 10 0 0 0
Valdosta 41 61 27 47 27 / 10 20 0 0 0
Cross City 43 66 30 49 25 / 10 20 0 0 0
Apalachicola 51 64 31 48 36 / 20 30 0 0 0
Small Craft Advisory from 11 AM Tuesday to 7 AM EST Wednesday for Coastal waters From Ochlockonee River to Apalachicola FL out to 60 NM.
Small Craft Advisory from 7 AM Tuesday to 7 AM EST Wednesday for Coastal waters from Apalachicola to Destin FL out 60 NM.