Alert archive / Mississippi / Mesoscale Discussions in 2021
Mesoscale Discussion 256
The Storm Prediction Center issued this mesoscale discussion at Mar 25, 2021, 1:24 PM CDT for 10 counties in Alabama; 22 counties in Mississippi. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 25, 2021, 1:24 PM CDT (18:24 UTC)
- Expired
- Mar 25, 2021, 3:30 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 50
All 32 counties
Colbert County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Lamar County, AL, Lawrence County, AL, Marion County, AL, Pickens County, AL, Sumter County, AL, Winston County, AL, Chickasaw County, MS, Choctaw County, MS, Clarke County, MS, Clay County, MS, Itawamba County, MS, Jasper County, MS, Kemper County, MS, Lauderdale County, MS, Lee County, MS, Lowndes County, MS, Monroe County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Pontotoc County, MS, Prentiss County, MS, Scott County, MS, Smith County, MS, Tishomingo County, MS, Union County, MS, Winston County, MS
The radar
The Columbus AFB radar (KGWX), 37 km from the middle of the area, began a volume at 18:29 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
Birmingham, AL (KBMX), launched 12:00Z, 6.4 hours before the alert went out and 140 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
- 54 J/kg
- Mixed-layer CIN
- -239 J/kg
- Mixed-layer LCL
- 507 m above ground
- 0-6 km bulk shear
- 65 kt
- 0-1 km storm-relative helicity
- 613 m²/s²
- 0-3 km storm-relative helicity
- 713 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.6
The text
As transmitted.
104
ACUS11 KWNS 251824
SWOMCD
SPC MCD 251824
ALZ000-MSZ000-252030-
Mesoscale Discussion 0256
NWS Storm Prediction Center Norman OK
0124 PM CDT Thu Mar 25 2021
Areas affected...much of eastern Mississippi into western Alabama
Concerning...Tornado Watch 50...
Valid 251824Z - 252030Z
The severe weather threat for Tornado Watch 50 continues.
SUMMARY...Storms are expected to intensify throughout the afternoon,
with several tornadic supercells possible including the threat of
strong tornadoes.
DISCUSSION...Areal coverage of thunderstorms has increased over the
past 2 hours across central and into eastern MS, where a very moist
and unstable air mass exists. Low-level winds have veered in the
wake of the warm advection storms to the northeast, which has
temporarily reduced SRH and made for straight hodographs. Indeed, a
few storms have become left movers recently with hail threat.
However, SRH will increase again over the next several hours as the
surface low develops to the northwest. This should result in an SRH
gradient over eastern MS and favorable parameters space for strong
tornadoes.
Current thinking is a few cells may consolidate into supercells out
of the larger area of storms. Additional storms are expected to form
along the front near the MS River as well. Strong southwest winds
aloft will bring all storms into an environment favorable for
tornadoes.
..Jewell.. 03/25/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BMX...HUN...MOB...MEG...JAN...
LAT...LON 34188715 33478747 32978769 32538797 32008835 31728872
31638993 33078933 33158932 33948915 34388913 34828862
34928804 34898736 34708702 34378707 34188715SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 24, 9:25 PM CDT | Mesoscale Discussion | SPC | Baldwin, Mobile, Washington | 65 min |
| Mar 25, 9:02 AM CDT | Mesoscale Discussion | SPC | Blount, Calhoun, Cherokee, Cleburne, Colbert, Cullman and 21 more | 118 min |
| Mar 25, 10:12 AM CDT | Mesoscale Discussion | SPC | Bibb, Blount, Colbert, Cullman, DeKalb, Etowah and 22 more | 3 hr |
| Mar 25, 10:58 AM CDT | Mesoscale Discussion | SPC | Colbert, Fayette, Franklin, Lamar, Lawrence, Marion and 2 more | 3 hr |
| Mar 25, 11:26 AM CDT | Tornado Watch | SPC | Autauga, Bibb, Blount, Calhoun, Chambers, Cherokee and 39 more | 9 hr |
| Mar 25, 12:28 PM CDT | Mesoscale Discussion | SPC | Bibb, Calhoun, Clay, Cleburne, Shelby, Talladega | 2 hr |
| Mar 25, 3:45 PM CDT | Mesoscale Discussion | SPC | Bibb, Chilton, Choctaw, Dallas, Greene, Hale and 8 more | 2 hr |
| Mar 25, 4:45 PM CDT | Mesoscale Discussion | SPC | Bibb, Chilton, Coosa, Perry, Shelby, Talladega | 60 min |
| Mar 25, 5:45 PM CDT | Mesoscale Discussion | SPC | Clay, Randolph | 60 min |
| Mar 25, 11:00 AM CDT | Mesoscale Discussion | SPC | Hancock, Harrison, Pearl River, Stone | 2 hr |
| Mar 25, 2:29 PM CDT | Mesoscale Discussion | SPC | Alcorn | 2 hr |
| Mar 25, 3:48 PM CDT | Tornado Watch | SPC | Alcorn | 7 hr |
Nearby
Mesoscale Discussions in Mississippi, 2021Mesoscale Discussions in Alabama, 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.