Alert archive / Georgia / Mesoscale Discussions in 2021
Mesoscale Discussion 542
The Storm Prediction Center issued this mesoscale discussion at May 4, 2021, 9:28 PM CDT for 13 counties in Florida; 30 counties in Georgia. It was in force for 92 min.
The area
The outline as issued.
The facts
- Issued
- May 4, 2021, 9:28 PM CDT (02:28 UTC)
- Expired
- May 4, 2021, 11:00 PM CDT
- In force
- 92 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 151
All 43 counties
Bay County, FL, Calhoun County, FL, Gadsden County, FL, Gulf County, FL, Holmes County, FL, Jackson County, FL, Jefferson County, FL, Leon County, FL, Liberty County, FL, Okaloosa County, FL, Wakulla County, FL, Walton County, FL, Washington County, FL, Baker County, GA, Ben Hill County, GA, Berrien County, GA, Bibb County, GA, Bleckley County, GA, Brooks County, GA, Colquitt County, GA, Cook County, GA, Crisp County, GA, Decatur County, GA, Dodge County, GA, Dougherty County, GA, Grady County, GA, Houston County, GA, Irwin County, GA, Jones County, GA, Laurens County, GA, Miller County, GA, Mitchell County, GA, Pulaski County, GA, Seminole County, GA, Telfair County, GA, Thomas County, GA, Tift County, GA, Turner County, GA, Twiggs County, GA, Wheeler County, GA, Wilcox County, GA, Wilkinson County, GA, Worth County, GA
The radar
The Ft Rucker radar (KEOX), 86 km from the middle of the area, began a volume at 02:30 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
Tallahassee Rgnl, FL (KTLH), launched 00:00Z, 2.5 hours before the alert went out and 114 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
- 1458 J/kg
- Mixed-layer CIN
- -7 J/kg
- Mixed-layer LCL
- 1099 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 97 m²/s²
- 0-3 km storm-relative helicity
- 134 m²/s²
- Significant tornado parameter
- 0.8
- Supercell composite
- 5.9
The text
As transmitted.
056
ACUS11 KWNS 050229
SWOMCD
SPC MCD 050228
GAZ000-FLZ000-ALZ000-050400-
Mesoscale Discussion 0542
NWS Storm Prediction Center Norman OK
0928 PM CDT Tue May 04 2021
Areas affected...Portions of the FL Panhandle...far southeastern
AL...and southern/central GA
Concerning...Severe Thunderstorm Watch 151...
Valid 050228Z - 050400Z
The severe weather threat for Severe Thunderstorm Watch 151
continues.
SUMMARY...An isolated strong to damaging wind threat continues in
the short term, but storm intensity should gradually decrease this
evening. Downstream watch issuance is not expected.
DISCUSSION...A long-lived MCS is beginning to show signs of
decreasing intensity over the past hour or so, with cloud top
temperatures warming in IR satellite imagery, lightning flash rates
diminishing, and reflectivity cores aloft weakening. With the
exception of the FL Panhandle, instability gradually wanes with
eastward extent into central GA based on the latest mesoanalysis
estimates. The southern portion of the line in far southeastern AL
and the FL Panhandle has become oriented more parallel to the mean
mid-level flow aloft, and has slowly decelerated. Still, isolated
strong to damaging winds around 50-60 mph may occur with any of the
stronger segments of the line over the next hour or so. A couple of
measured wind gusts around 50 mph have recently occurred, and the
ASOS in Albany GA reported a wind gust of 62 mph at 0211Z. Given the
expectation that overall storm intensity should continue to decrease
through the remainder of the evening, downstream watch issuance is
not expected.
..Gleason.. 05/05/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...JAX...FFC...TAE...MOB...
LAT...LON 30608667 31258496 31778385 32368365 32918386 33128392
33018307 32538253 31198305 30158414 29638508 30208590
30368640 30608667SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 4, 7:38 PM CDT | Mesoscale Discussion | SPC | Baker, Calhoun, Chattahoochee, Clay, Crawford, Crisp and 24 more | 97 min |
Nearby
Mesoscale Discussions in Georgia, 2021Mesoscale Discussions in Florida, 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.