Alert archive / Florida / Mesoscale Discussions in 2021
Mesoscale Discussion 362
The Storm Prediction Center issued this mesoscale discussion at Apr 10, 2021, 3:13 PM EDT for 14 counties in Florida; Charlton County, Clinch County, Ware County, Georgia. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 10, 2021, 3:13 PM EDT (19:13 UTC)
- Expired
- Apr 10, 2021, 5:15 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Alachua County, FL, Baker County, FL, Bradford County, FL, Citrus County, FL, Clay County, FL, Columbia County, FL, Duval County, FL, Gilchrist County, FL, Levy County, FL, Marion County, FL, Nassau County, FL, Putnam County, FL, Suwannee County, FL, Union County, FL, Charlton County, GA, Clinch County, GA, Ware County, GA
The radar
The Jacksonville radar (KJAX), 80 km from the middle of the area, began a volume at 19:13 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, 7.2 hours before the alert went out and 81 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
- 159 J/kg
- Mixed-layer CIN
- -225 J/kg
- Mixed-layer LCL
- 965 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- 91 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
929
ACUS11 KWNS 101913
SWOMCD
SPC MCD 101913
FLZ000-GAZ000-102115-
Mesoscale Discussion 0362
NWS Storm Prediction Center Norman OK
0213 PM CDT Sat Apr 10 2021
Areas affected...southeastern Georgia and northern Florida
Concerning...Severe potential...Watch unlikely
Valid 101913Z - 102115Z
Probability of Watch Issuance...20 percent
SUMMARY...A couple of stronger storms withing an evolving convective
band may produce locally gusty winds or a brief tornado. WW
issuance is not expected at this time.
DISCUSSION...Latest radar loop shows an uptick in the intensity of
the ongoing convective band moving across northern Florida/southern
Georgia. This has occurred as diurnal heating of the modestly moist
boundary layer has pushed mixed-layer CAPE values up into the 500 to
1000 J/kg range ahead of the band, and west of the now inland
sea-breeze boundary.
With storms moving east-northeastward at roughly 35 kt, and a mixed
sub-cloud layer, gusty winds can be expected within the band of
storms. A stronger gust or two -- possibly approaching severe
levels, cannot be ruled out; nor can a brief QLCS-type spin-up, as
storms reach peak intensity over the next 1-2 hours. Interaction of
this band of storms with the sea-breeze front may support a
further/brief uptick in convective intensity, before storms begin
moving offshore later this afternoon.
..Goss/Thompson.. 04/10/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MLB...TBW...JAX...TAE...
LAT...LON 31268260 31168224 31018197 30308160 29548139 28798202
28798248 28918287 29158308 29928293 30238302 31288274
31268260SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 10, 2:52 AM EDT | Mesoscale Discussion | SPC | Escambia, Holmes, Okaloosa, Santa Rosa, Walton, Washington | 113 min |
| Apr 10, 3:30 AM EDT | Tornado Watch | SPC | Bay, Calhoun, Escambia, Gulf, Holmes, Jackson and 4 more | 8 hr |
| Apr 10, 5:06 AM EDT | Mesoscale Discussion | SPC | Escambia, Holmes, Okaloosa, Santa Rosa, Walton, Washington | 114 min |
| Apr 10, 8:10 AM EDT | Mesoscale Discussion | SPC | Bay, Calhoun, Escambia, Franklin, Gadsden, Gulf and 8 more | 2 hr |
| Apr 10, 9:58 AM EDT | Mesoscale Discussion | SPC | Bay, Calhoun, Dixie, Franklin, Gadsden, Gulf and 9 more | 92 min |
| Apr 10, 10:20 AM EDT | Tornado Watch | SPC | Dixie, Franklin, Gadsden, Jefferson, Lafayette, Leon and 4 more | 4 hr |
| Apr 10, 11:49 AM EDT | Mesoscale Discussion | SPC | Jefferson, Lafayette, Leon, Madison, Taylor, Wakulla | 116 min |
Nearby
Mesoscale Discussions in Florida, 2021Mesoscale Discussions in Georgia, 2021Every mesoscale discussion in 2021
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.