Near Term [Through Today]...
Active MCS across Southern Alabama will continue to move slowly
east southeastward today across the Florida Panhandle and adjacent
Local hi-resolution guidance shows the bulk of the rain associated with this MCS moving across our Alabama and Florida Panhandle zones before spreading offshore.
Surface data show that a rather stable airmass is in place across the region, so the potential for severe weather is very low.
However, overall movement of this system hasn`t been especially fast and with additional shower and thunderstorm developing south of the Florida Panhandle moving northeastward ahead of the main line, locally heavy rainfall could become a problem.
As a result, have posted a flash flood watch for our western counties through this evening.
This is in line with some of the hi-res output that indicates as much as 6 to 7 inches of rain in some locations by the end of the day.
While this is certainly on the high side, the average of the guidance suggests 2 to 4 inches of rain, with locally heavier amounts are certainly possible.
Given the wet antecedent conditions, these average amounts would likely be sufficient to cause some minor flood problems across the Florida Panhandle.
Short Term [Tonight Through Sunday]...
In what seems to be the year of the east coast trough, another 500 mb trough will translate eastward over the Southeast this weekend.
Ahead of this trough (and associated cold front) we expect numerous showers and thunderstorms across our forecast area late tonight through Saturday.
The rain will end from west to east Saturday afternoon and evening as the surface cold front moves through.
Sunny skies and a drier, slightly cooler airmass are expected for Sunday.
There is good agreement among the GFS, ECMWF, and SREF members that west winds will increase to around 50 KT at 500 mb on
Saturday, and the NWP guidance consensus puts the MLCAPE around 1000 J/kg.
The combination of these values would suggest at least a "slight" risk of isolated severe storms, and the calibrated severe storm probs from the 21 UTC SREF, as well as various local guidance tools, agree with this.
If the GFS verifies, the main severe mode would be damaging wind gusts along bowing QLCS segments, and possibly even severe hail (with 850-700 mb lapse rates exceeding 6.5 deg/km).
The ECMWF solution would indicate at least a small threat of tornadoes as well, as unlike the GFS, it forecasts a 35 kt 850 mb jet ahead of the cold front.
For now the risk is only "slight" because the GFS and ECMWF forecast a significant mid tropospheric dry slot developing immediately ahead of the cold front.
While this could actually help increase CAPE (more sun), it may also tend to squelch deep moist convection immediately ahead of the cold front.
In other words, there may be a nearly rain- free zone between the rain band (that develops well ahead of the cold front late tonight and Saturday morning) and the surface cold front, which will lag behind by a few hours.
Hopefully the day shift will be better able to assess this as they will have access to more high-res NWP guidance.
Long Term [Sunday Night Through Friday]...
For the work week, temperatures will be in the mid to upper 70s.
Onshore flow returns Wednesday bringing more moisture to the
The next chance for rain will be Thursday with the arrival of the next system.
Rain and thunderstorms will overspread the region today impacting
all terminals with at least MVFR cigs/vsbys through afternoon.
IFR conditions are possible in the heavier storms today, especially at
A lull in shower and thunderstorm activity is expected after midnight, however, ceilings will likely remain in the MVFR range.
Winds and seas were still near or at advisory levels across much of our marine area, and we think that this will continue until early afternoon.
Moderate onshore winds and seas will persist through Saturday evening, with advisory conditions possibly returning behind the cold front Saturday night and early Sunday.
Tides were about 1 ft above normal, and this will likely continue into tonight. It does not appear that the storm tides will cause flooding.
With a storm system moving into the region, relative humidity values
will stay well above critical levels today and Saturday.
Drier air will arrive on Sunday in the wake of a cold front but red flag
conditions are not expected at this time.
We expect most rain gages to get 1 to 3 inches of rain through
Saturday, with the highest values likely in the FL Panhandle.
There is a 10% chance of flash flooding (within 25 miles of a point) through tonight west of the Apalachicola River, mainly near the FL Panhandle coast.
For now we don`t think that this is high enough to warrant a flood watch, but we will certainly monitor upstream convective trends closely this morning.
There is a good chance that several local river forecast points will go back to at least action stage late this weekend or next week.
This appears most likely in the lower basins where we expect
the heaviest rain.
Preliminary Point Temps/PoPs...
Tallahassee 72 62 79 46 75 / 90 50 60 10 0
Panama City 71 62 75 51 71 / 100 60 60 0 0
Dothan 71 60 78 45 72 / 100 70 60 0 0
Albany 73 60 78 45 73 / 100 60 60 10 0
Valdosta 75 60 82 47 72 / 90 50 60 10 0
Cross City 76 62 81 50 74 / 70 70 60 20 0
Apalachicola 69 63 75 50 70 / 90 60 60 0 0
FL...Flash Flood Watch until 8 PM EDT /7 PM CDT/ this evening for
Calhoun-Central Walton-Coastal Bay-Coastal Gulf-Holmes-Inland Bay-Inland Gulf-Inland Walton-Jackson-South Walton-Washington.
AL...Flash Flood Watch until 7 PM CDT this evening for Coffee-Dale-
GM...Small Craft Advisory until 2 PM EDT this afternoon 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.