Alert archive / Arkansas / Mesoscale Discussions in 2015

Mesoscale Discussion 389

April 19, 201538 counties in Arkansas; 21 parishes in Louisiana

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2015, 9:41 PM CDT for 38 counties in Arkansas; 21 parishes in Louisiana. It was in force for 64 min.

The area

The outline as issued.

The facts

Issued: Apr 19, 2015, 9:41 PM CDT (02:41 UTC)
Expired: Apr 19, 2015, 10:45 PM CDT
In force: 64 min
Issued by: the Storm Prediction Center

All 59 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Cleburne County, AR, Cleveland County, AR, Columbia County, AR, Conway County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Faulkner County, AR, Garland County, AR, Grant County, AR, Hot Spring County, AR, Jackson County, AR, Jefferson County, AR, Lafayette County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Monroe County, AR, Nevada County, AR, Ouachita County, AR, Perry County, AR, Poinsett County, AR, Pope County, AR, Prairie County, AR, Pulaski County, AR, Saline County, AR, St. Francis County, AR, Union County, AR, Van Buren County, AR, White County, AR, Woodruff County, AR, Bienville Parish, LA, Bossier Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Franklin Parish, LA, Grant Parish, LA, Jackson Parish, LA, LaSalle Parish, LA, Lincoln Parish, LA, Morehouse Parish, LA, Natchitoches Parish, LA, Ouachita Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA

The radar

The Shreveport radar (KSHV), 133 km from the middle of the area, began a volume at 02:43 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 (KBAD), launched 00:00Z, 2.7 hours before the alert went out and 124 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: 1179 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 1386 m above ground
0-6 km bulk shear: 56 kt
0-1 km storm-relative helicity: 126 m²/s²
0-3 km storm-relative helicity: 204 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 8.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 19, 7:09 PM CDT	Mesoscale Discussion	SPC	Arkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 32 more	2 hr
Apr 19, 10:16 PM CDT	Mesoscale Discussion	SPC	Chicot, Clay, Craighead, Crittenden, Cross, Desha and 6 more	59 min
Apr 19, 8:02 PM CDT	Tornado Watch	SPC	Avoyelles, Evangeline, Rapides, Vernon	5 hr

Nearby

Mesoscale Discussions in Arkansas, 2015 Mesoscale Discussions in Louisiana, 2015 Every mesoscale discussion in 2015

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.