Alert archive / Mississippi / Mesoscale Discussions in 2023
Mesoscale Discussion 421
The Storm Prediction Center issued this mesoscale discussion at Mar 31, 2023, 10:23 PM CDT for Desha County, Arkansas; 25 counties in Mississippi. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 31, 2023, 10:23 PM CDT (03:23 UTC)
- Expired
- Apr 1, 2023, 12:30 AM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 97...99
All 26 counties
Desha County, AR, Benton County, MS, Bolivar County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Coahoma County, MS, DeSoto County, MS, Grenada County, MS, Lafayette County, MS, Lee County, MS, Leflore County, MS, Marshall County, MS, Montgomery County, MS, Panola County, MS, Pontotoc County, MS, Prentiss County, MS, Quitman County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tippah County, MS, Tunica County, MS, Union County, MS, Webster County, MS, Yalobusha County, MS
The radar
The Columbus AFB radar (KGWX), 128 km from the middle of the area, began a volume at 03:24 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Little Rock, AR (KLZK), launched 00:00Z, 3.4 hours before the alert went out and 93 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
- 668 J/kg
- Mixed-layer CIN
- -59 J/kg
- Mixed-layer LCL
- 1086 m above ground
- 0-6 km bulk shear
- 75 kt
- 0-1 km storm-relative helicity
- 234 m²/s²
- 0-3 km storm-relative helicity
- 244 m²/s²
- Significant tornado parameter
- 0.9
- Supercell composite
- 6.3
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 31, 7:42 PM CDT | Mesoscale Discussion | SPC | Ashley, Chicot | 2 hr |
| Mar 31, 8:24 PM CDT | Tornado Watch | SPC | Ashley, Chicot, Union | 8 hr |
| Mar 31, 11:20 PM CDT | Mesoscale Discussion | SPC | Alcorn, Itawamba, Prentiss, Tippah, Tishomingo | 115 min |
| Mar 31, 11:59 PM CDT | Tornado Watch | SPC | Alcorn, Benton, Calhoun, Chickasaw, Itawamba, Lafayette and 10 more | 6 hr |
| Apr 1, 1:13 AM CDT | Mesoscale Discussion | SPC | Calhoun, Chickasaw, Itawamba, Lee, Monroe, Pontotoc and 3 more | 92 min |
| Apr 1, 2:03 AM CDT | Mesoscale Discussion | SPC | Attala, Carroll, Choctaw, Claiborne, Clay, Copiah and 23 more | 87 min |
| Apr 1, 2:40 AM CDT | Tornado Watch | SPC | Clarke, Clay, Jasper, Kemper, Lauderdale, Leake and 9 more | 4 hr |
Nearby
Mesoscale Discussions in Mississippi, 2023Mesoscale Discussions in Arkansas, 2023Every mesoscale discussion in 2023
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.