Alert archive / Arkansas / Mesoscale Discussions in 2020

Mesoscale Discussion 475

April 24, 202035 counties in Arkansas; 19 parishes in Louisiana

The Storm Prediction Center issued this mesoscale discussion at Apr 24, 2020, 10:17 PM CDT for 35 counties in Arkansas; 19 parishes in Louisiana. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued: Apr 24, 2020, 10:17 PM CDT (03:17 UTC)
Expired: Apr 25, 2020, 12:15 AM CDT
In force: 118 min
Issued by: the Storm Prediction Center

All 54 counties

Arkansas County, AR, Ashley County, AR, Baxter County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Cleburne County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Fulton County, AR, Grant County, AR, Hot Spring County, AR, Independence County, AR, Izard County, AR, Jefferson County, AR, Lincoln County, AR, Lonoke County, AR, Monroe County, AR, Ouachita County, AR, Perry County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, Searcy County, AR, Stone County, AR, Union County, AR, Van Buren County, AR, White County, AR, Yell County, AR, Bienville Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Richland Parish, LA, Tensas Parish, LA, Union Parish, LA, West Carroll Parish, LA, Winn Parish, LA

The radar

The Little Rock radar (KLZK), 92 km from the middle of the area, began a volume at 03:19 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

Shreveport, LA (KSHV), launched 00:00Z, 3.3 hours before the alert went out and 205 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: 319 J/kg
Mixed-layer CIN: -165 J/kg
Mixed-layer LCL: 1943 m above ground
0-6 km bulk shear: 72 kt
0-1 km storm-relative helicity: 160 m²/s²
0-3 km storm-relative helicity: 350 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 6.1

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 24, 7:19 PM CDT	Mesoscale Discussion	SPC	Clark, Columbia, Hempstead, Howard, Lafayette, Little River and 6 more	101 min
Apr 24, 8:31 PM CDT	Severe Thunderstorm Watch	SPC	Arkansas, Ashley, Boone, Bradley, Calhoun, Chicot and 30 more	5 hr
Apr 24, 9:26 PM CDT	Mesoscale Discussion	SPC	Columbia, Lafayette, Miller	94 min
Apr 24, 7:43 PM CDT	Mesoscale Discussion	SPC	Bienville, Caldwell, Claiborne, Grant, Jackson, Lincoln and 6 more	62 min

Nearby

Mesoscale Discussions in Arkansas, 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.