Alert archive / Mississippi / Mesoscale Discussions in 2020

Mesoscale Discussion 365

April 12, 2020Lamar County, Marion County, Alabama; Madison Parish, Tensas Parish, Louisiana; 29 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2020, 5:44 PM CDT for Lamar County, Marion County, Alabama; Madison Parish, Tensas Parish, Louisiana; 29 counties in Mississippi. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued: Apr 12, 2020, 5:44 PM CDT (22:44 UTC)
Expired: Apr 12, 2020, 7:15 PM CDT
In force: 91 min
Issued by: the Storm Prediction Center

All 33 counties

Lamar County, AL, Marion County, AL, Madison Parish, LA, Tensas Parish, LA, Attala County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Itawamba County, MS, Leake County, MS, Lee County, MS, Leflore County, MS, Lowndes County, MS, Madison County, MS, Monroe County, MS, Montgomery County, MS, Noxubee County, MS, Oktibbeha County, MS, Pontotoc County, MS, Sharkey County, MS, Sunflower County, MS, Tallahatchie County, MS, Warren County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 86 km from the middle of the area, began a volume at 22:44 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.

Severe Thunderstorm Watch 114Apr 12, 8:20 PM CDT

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 10.7 hours before the alert went out and 80 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 323 J/kg
Mixed-layer CIN: -279 J/kg
Mixed-layer LCL: 625 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 379 m²/s²
0-3 km storm-relative helicity: 562 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 12, 1:45 PM CDT	Mesoscale Discussion	SPC	Autauga, Bibb, Blount, Calhoun, Cherokee, Chilton and 33 more	90 min
Apr 12, 3:20 PM CDT	Tornado Watch	SPC	Bibb, Blount, Calhoun, Cherokee, Chilton, Clay and 30 more	8 hr
Apr 12, 3:38 PM CDT	Mesoscale Discussion	SPC	Fayette, Greene, Lamar, Pickens, Sumter, Tuscaloosa and 1 more	97 min
Apr 12, 3:53 PM CDT	Mesoscale Discussion	SPC	Clarke, Washington	97 min
Apr 12, 4:38 PM CDT	Tornado Watch PDS	SPC	Autauga, Baldwin, Bibb, Calhoun, Chilton, Choctaw and 22 more	7 hr
Apr 12, 4:54 PM CDT	Mesoscale Discussion	SPC	Choctaw	66 min
Apr 12, 5:14 PM CDT	Mesoscale Discussion	SPC	Blount, Calhoun, Cherokee, Cleburne, Cullman, DeKalb and 13 more	91 min
Apr 12, 5:52 AM CDT	Tornado Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	8 hr
Apr 12, 7:18 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 13 more	87 min
Apr 12, 9:30 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	90 min
Apr 12, 10:24 AM CDT	Mesoscale Discussion	SPC	Catahoula, Concordia, East Carroll, Franklin, Madison, Morehouse and 3 more	96 min
Apr 12, 10:41 AM CDT	Tornado Watch PDS	SPC	Catahoula, Concordia, East Carroll, Franklin, Madison, Morehouse and 3 more	10 hr
Apr 12, 12:03 PM CDT	Mesoscale Discussion	SPC	East Carroll, Franklin, Madison, Morehouse, Richland, West Carroll	87 min
Apr 12, 1:02 PM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Livingston and 12 more	118 min
Apr 12, 1:24 PM CDT	Tornado Watch	SPC	Acadia, Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia and 16 more	9 hr
Apr 12, 5:27 PM CDT	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Livingston and 6 more	63 min
Apr 12, 5:59 PM CDT	Severe Thunderstorm Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, Jackson and 5 more	4 hr
Apr 12, 6:14 PM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, Lincoln, Red River and 1 more	91 min
Apr 12, 1:40 PM CDT	Mesoscale Discussion	SPC	Attala, Choctaw, Hinds, Holmes, Kemper, Lauderdale and 10 more	95 min
Apr 12, 3:52 PM CDT	Mesoscale Discussion	SPC	Covington, Jefferson Davis, Jones, Marion	23 min
Apr 12, 4:26 PM CDT	Mesoscale Discussion	SPC	Covington, Jasper, Jones	34 min

Nearby

Mesoscale Discussions in Mississippi, 2020 Mesoscale Discussions in Alabama, 2020 Mesoscale Discussions in Louisiana, 2020 Every mesoscale discussion in 2020

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.