Alert archive / Mississippi / Mesoscale Discussions in 2019

Mesoscale Discussion 322

April 13, 20196 parishes in Louisiana; 16 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2019, 12:53 PM CDT for 6 parishes in Louisiana; 16 counties in Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 13, 2019, 12:53 PM CDT (17:53 UTC)
Expired: Apr 13, 2019, 3:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 60%

All 22 counties

East Carroll Parish, LA, Franklin Parish, LA, Madison Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Attala County, MS, Carroll County, MS, Claiborne County, MS, Copiah County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Leake County, MS, Madison County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Warren County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 67 km from the middle of the area, began a volume at 17:53 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.

Tornado Watch 54Apr 13, 2:20 PM CDT

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 5.9 hours before the alert went out and 57 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: 29 J/kg
Mixed-layer CIN: -284 J/kg
Mixed-layer LCL: 491 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 515 m²/s²
0-3 km storm-relative helicity: 933 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 5.6

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, 10:14 PM CDT	Mesoscale Discussion	SPC	Beauregard, Calcasieu, Vernon	3 hr
Apr 13, 1:52 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Catahoula, Claiborne and 20 more	113 min
Apr 13, 9:49 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, De Soto, Natchitoches, Red River and 2 more	56 min
Apr 13, 10:01 AM CDT	Severe Thunderstorm Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	5 hr
Apr 13, 11:26 AM CDT	Tornado Watch	SPC	Allen, Avoyelles, Beauregard, Bienville, Bossier, Caddo and 18 more	8 hr
Apr 13, 11:52 AM CDT	Mesoscale Discussion	SPC	De Soto, Natchitoches, Red River, Sabine, Vernon	83 min
Apr 13, 1:38 PM CDT	Mesoscale Discussion	SPC	Allen, Avoyelles, Beauregard, Catahoula, De Soto, Grant and 7 more	97 min
Apr 13, 2:20 PM CDT	Tornado Watch	SPC	Catahoula, Concordia, East Carroll, East Feliciana, Franklin, Madison and 7 more	10 hr
Apr 13, 3:39 PM CDT	Mesoscale Discussion	SPC	Allen, Avoyelles, Beauregard, Bienville, Bossier, Calcasieu and 25 more	96 min
Apr 13, 4:35 PM CDT	Mesoscale Discussion	SPC	Caldwell, Franklin, Grant, LaSalle, Madison, Richland and 2 more	55 min
Apr 13, 5:04 PM CDT	Mesoscale Discussion	SPC	Clarke, Kemper, Lauderdale, Lowndes, Neshoba, Newton and 3 more	2 hr
Apr 13, 6:13 PM CDT	Mesoscale Discussion	SPC	Attala, Leake, Madison, Yazoo	62 min

Nearby

Mesoscale Discussions in Mississippi, 2019 Mesoscale Discussions in Louisiana, 2019 Every mesoscale discussion in 2019

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.