Alert archive / Mississippi / Mesoscale Discussions in 2019

Mesoscale Discussion 283

April 7, 2019Ashley County, Chicot County, Arkansas; 12 parishes in Louisiana; 21 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 7, 2019, 6:44 PM CDT for Ashley County, Chicot County, Arkansas; 12 parishes in Louisiana; 21 counties in Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Apr 7, 2019, 6:44 PM CDT (23:44 UTC)
Expired: Apr 7, 2019, 8:45 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 35 counties

Ashley County, AR, Chicot County, AR, Ascension Parish, LA, East Baton Rouge Parish, LA, East Carroll Parish, LA, East Feliciana Parish, LA, Livingston Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Richland Parish, LA, Saint Helena Parish, LA, Tangipahoa Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Copiah County, MS, Franklin County, MS, Hinds County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Lawrence County, MS, Lincoln County, MS, Madison County, MS, Pike County, MS, Rankin County, MS, Sharkey County, MS, Simpson County, MS, Walthall County, MS, Warren County, MS, Washington County, MS, Wilkinson County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 116 km from the middle of the area, began a volume at 23:47 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 44Apr 7, 7:45 PM CDT

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 11.7 hours before the alert went out and 113 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: 1228 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 597 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 128 m²/s²
0-3 km storm-relative helicity: 208 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 3.3

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 7, 5:29 AM CDT	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Calhoun, Clark, Cleveland and 24 more	2 hr
Apr 7, 10:45 AM CDT	Mesoscale Discussion	SPC	Chicot, Desha	60 min
Apr 7, 1:11 PM CDT	Severe Thunderstorm Watch	SPC	Columbia, Hempstead, Lafayette, Miller, Nevada, Union	6 hr
Apr 7, 1:13 PM CDT	Mesoscale Discussion	SPC	Chicot	2 hr
Apr 7, 3:41 PM CDT	Severe Thunderstorm Watch	SPC	Ashley, Chicot	6 hr
Apr 6, 7:44 PM CDT	Mesoscale Discussion	SPC	Bienville, Caldwell, De Soto, Franklin, Grant, Jackson and 11 more	2 hr
Apr 7, 12:27 PM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Beauregard, Bienville, Calcasieu and 24 more	93 min
Apr 7, 2:49 PM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Beauregard, Bienville, Calcasieu, Caldwell and 17 more	86 min
Apr 6, 7:09 PM CDT	Mesoscale Discussion	SPC	Chickasaw, Clay, Itawamba, Kemper, Lowndes, Monroe and 4 more	96 min
Apr 7, 5:36 PM CDT	Mesoscale Discussion	SPC	Lowndes, Noxubee, Oktibbeha	114 min

Nearby

Mesoscale Discussions in Mississippi, 2019 Mesoscale Discussions in Louisiana, 2019 Mesoscale Discussions in Arkansas, 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.