Near Term [Through Today]...
After some patchy fog (which was fairly unexpected) burns off once
again this morning, another mostly sunny and unseasonably hot
day is expected across the region.
Despite a very slight drop in 850 mb temps (from about 20 degrees C to 18-19 degrees depending on the model chosen), the 1000-700mb Mean Layer Vector Wind (MLVW) which most strongly influences our sea breeze circulation will still be out of the NW at 10 to 15 kts (and will be strongest over eastern portions of the CWA).
Therefore, believe this offshore flow will delay the inland penetration of the still dry sea breeze front long enough to allow for the hottest day of the season thus far at TLH, VLD, and ABY, which is just a touch above the high temps reached on Thursday.
Fcst highs today are respectively 97 at TLH, 98 at VLD, and 95 at ABY.
Even though water tables are very high, still believe that one more dry day could make the difference in slightly drier soil moisture to allow for these hot temperatures.
Closer to the coast, still expect highs in the lower 80s right at the beaches to the middle 80s to near 90 just inland before the sea breeze front finally overtakes the beaches and nearshore areas.
Short Term [Tonight Through Sunday]...
We should see a return of showers and thunderstorms at some point
The deep ridging that has been in place over our area for much of the week will begin to break down.
A mid-upper level shortwave - evident on water vapor loops over Michigan - will dig to off the mid-Atlantic coast by Saturday morning, and that will contribute to gradually falling heights all the way down
the east coast to our forecast area.
A slow-moving surface cold front that currently stretches from the Delmarva to the Ozarks will begin pushing south, nearing our area by Saturday Night or Sunday.
The breakdown of the ridge accompanied by some low-level forcing should be sufficient to create some thunderstorms by Sunday afternoon.
Models were in fairly good agreement on placing the bulk of QPF in the eastern half of our area Sunday afternoon and evening and PoPs were bumped up in those areas to 30-40%.
A few models hinted at some overnight convection from N/C AL into C
GA on Saturday Night as the surface cold front approaches and a
weak shortwave aloft moves east, but QPF was generally very light.
Given the lack of consistency, and the bulk of the forcing remaining north of our area, we opted not to include any mention of showers and thunderstorms prior to 15Z Sunday.
There is a continuum of possibilities regarding convective coverage and intensity on Sunday afternoon and evening, and it seems to be largely tied to surface dewpoints and resulting instability levels.
The NAM has the highest dewpoints, and therefore shows very high instability levels, with the GFS adopting more of a "middle ground" and the ECMWF drier.
With a lack of significant forcing mechanisms for convective development, it makes sense that the coverage would largely be tied to the instability levels.
For now, it seems as though the NAM may be too high with its forecast dewpoints, so we have adopted a consensus approach.
However, it should be noted that if the NAM was correct (dewpoints around 70F) - thunderstorms Sunday afternoon and evening could be more numerous, and stronger, than we are currently forecasting.
Even using the more tempered GFS solution would offer a chance of a few stronger storms.
Instability levels would still be fairly high, but 0-6km wind shear of just 20-30 knots could be a limiting factor.
Model consensus shows a gradual decrease in 850mb temperatures
through the period as the cold front approaches.
While this won`t change the observed surface temperatures from being hot overall, it should lead to slightly lower afternoon high temperatures (Saturday: 92-94, and Sunday: 90-93).
Long Term [Sunday Night Through Friday]...
The GFS & ECMWF are in generally good agreement in building a 500
mb ridge over our forecast area through Wednesday.
On Wednesday & Thursday they continued to diverge as the ECMWF maintains this ridge while the GFS develops an unusual-looking, east-west oriented trough along the Gulf Coast.
The MOS from both models have 20-30% PoPs across the eastern half of our forecast area through Tuesday, as this region will have a little more deep layer moisture and perhaps some weak Q-G forcing.
On Wednesday & Thursday the GFS solution suggests a wetter pattern spread evenly across our region, while the ECMWF solution would only allow for isolated afternoon/evening storms.
Our forecast, as usual, will be in between the two models.
Despite the model differences later next week, both sets of MOS are in good agreement for temperatures.
We expect near-climo temperatures with highs in the lower 90s and lows in the 60s.
With virtually no guidance at all supporting any fog (including the very reliable HRRR), was inclined to leave VFR conditions throughout the period.
However, just before the 06Z TAF issuance, noticed ECP and VLD beginning to drop towards MVFR levels, so did put a 3 hr window of IFR level VIS at ECP overnight.
Elsewhere, did leave VFR levels in place through 06Z Sat., but slightly higher dewpoints Friday night could result in more widespread MVFR level fog into early Sat. morning.
Also, could once again experience gusty W to SW winds at the
With high pressure situated near the northeast Gulf of Mexico, a
pattern of relatively weak winds should persist for the entire forecast period.
Winds should remain under 15 knots with seas 2 feet or less.
An isolated thunderstorm or two cannot be ruled out from Apalachee Bay to along the coasts of Taylor and Dixie Counties into early next week.
Although the hot and dry weather will continue for a couple of more days, no red flag concerns are expected well into next week.
All area river points are below flood stage.
However, elevated flows persist on many, with above normal soil moisture and groundwater levels over much of the area.
Flows have been slowly decreasing, though, thanks to a stretch of dry weather.
Rain chances should return on Sunday.
Most of the rain chances in the next seven days should be associated with isolated to scattered showers and thunderstorms - unlikely to produce widespread flooding.
However, some of the storms could be slow-moving, so localized flooding problems could develop, especially given the ongoing above normal soil moisture levels.
Preliminary Point Temps/PoPs...
Tallahassee 97 67 94 68 93 / 0 0 10 10 30
Panama City 87 71 87 70 87 / 0 0 0 10 10
Dothan 94 67 93 68 93 / 0 0 10 10 20
Albany 95 68 94 68 92 / 0 0 10 10 30
Valdosta 98 67 95 69 92 / 0 0 10 10 40
Cross City 94 68 94 68 91 / 0 0 10 10 30
Apalachicola 88 70 88 70 87 / 0 0 0 0 10