Alert archive / Florida / Mesoscale Discussions in 2024
Mesoscale Discussion 2113
The Storm Prediction Center issued this mesoscale discussion at Sep 26, 2024, 11:20 AM CDT for 7 counties in Florida. It was in force for 115 min.
The area
The outline as issued.
The facts
- Issued
- Sep 26, 2024, 11:20 AM CDT (16:20 UTC)
- Expired
- Sep 26, 2024, 1:15 PM CDT
- In force
- 115 min
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 685
Counties Calhoun County, FL, Franklin County, FL, Gadsden County, FL, Gulf County, FL, Jackson County, FL, Liberty County, FL, Wakulla County, FL
The radar
The Tallahassee radar (KTLH), 92 km from the middle of the area, began a volume at 16:20 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
The nearest sounding before it
Jacksonville, FL (KJAX), launched 12:00Z, 4.3 hours before the alert went out and 326 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 637 J/kg
- Mixed-layer CIN
- -16 J/kg
- Mixed-layer LCL
- 802 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 181 m²/s²
- 0-3 km storm-relative helicity
- 250 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 4.6
The text
As transmitted.
574
ACUS11 KWNS 261621
SWOMCD
SPC MCD 261620
FLZ000-261815-
Mesoscale Discussion 2113
NWS Storm Prediction Center Norman OK
1120 AM CDT Thu Sep 26 2024
Areas affected...central portions of the Florida Panhandle
Concerning...Tornado Watch 685...
Valid 261620Z - 261815Z
The severe weather threat for Tornado Watch 685 continues.
SUMMARY...Local risk for brief tornadoes will continue -- with
greatest short-term potential over central portions of the Florida
Panhandle.
DISCUSSION...Latest surface analysis reveals a nearly stationary
north-south trough -- acting as a pseudo warm front and, as such,
source of enhanced low-level vorticity -- extending from the
Franklin/Gulf County vicinity on the Florida Coast, northward across
far western Georgia and into the southern Appalachians. This
boundary reflects the discontinuity between the moist/tropical
airmass to the east, and the continental airmass to the west.
Several/continued brief low-level spin-ups have been observed over
the past couple of hours within this zone, and expect this local
enhancement of tornado potential to continue over the next couple of
hours, given increasingly favorably low-level flow and the nearly
stationary character of this north-south boundary.
..Goss.. 09/26/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TAE...
LAT...LON 29938539 30858521 30558448 29118399 28878488 29298555
29938539SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 26, 3:46 AM CDT | Mesoscale Discussion | SPC | Broward, Collier, Glades, Hendry, Miami-Dade, Monroe and 1 more | 2 hr |
| Sep 26, 5:42 AM CDT | Tornado Watch | SPC | Brevard, Broward, Charlotte, Citrus, Collier, DeSoto and 27 more | 13 hr |
| Sep 26, 8:07 AM CDT | Mesoscale Discussion | SPC | Brevard, Broward, Charlotte, Collier, DeSoto, Glades and 16 more | 113 min |
| Sep 26, 9:12 AM CDT | Mesoscale Discussion | SPC | Alachua, Baker, Bay, Bradford, Calhoun, Clay and 25 more | 63 min |
| Sep 26, 9:49 AM CDT | Tornado Watch | SPC | Alachua, Baker, Bay, Bradford, Calhoun, Clay and 24 more | 11 hr |
| Sep 26, 11:32 AM CDT | Mesoscale Discussion | SPC | Brevard, Broward, Charlotte, Citrus, Collier, DeSoto and 27 more | 118 min |
| Sep 26, 2:14 PM CDT | Mesoscale Discussion | SPC | Charlotte, Citrus, Collier, DeSoto, Glades, Hardee and 12 more | 2 hr |
| Sep 26, 2:40 PM CDT | Mesoscale Discussion | SPC | Bay, Calhoun, Columbia, Dixie, Franklin, Gadsden and 12 more | 2 hr |
| Sep 26, 5:39 PM CDT | Mesoscale Discussion | SPC | Nassau | 5 hr |
| Sep 26, 6:02 PM CDT | Mesoscale Discussion | SPC | Alachua, Baker, Bradford, Charlotte, Citrus, Clay and 38 more | 88 min |
| Sep 26, 6:50 PM CDT | Tornado Watch | SPC | Alachua, Baker, Bradford, Brevard, Charlotte, Citrus and 35 more | 9 hr |
Nearby
Mesoscale Discussions in Florida, 2024Every mesoscale discussion in 2024
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.