Alert archive / Texas / Mesoscale Discussions in 2020

Mesoscale Discussion 348

April 12, 202019 parishes in Louisiana; Warren County, Mississippi; 26 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2020, 7:18 AM CDT for 19 parishes in Louisiana; Warren County, Mississippi; 26 counties in Texas. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued: Apr 12, 2020, 7:18 AM CDT (12:18 UTC)
Expired: Apr 12, 2020, 8:45 AM CDT
In force: 87 min
Issued by: the Storm Prediction Center

All 46 counties

Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Caldwell Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, Franklin Parish, LA, Jackson Parish, LA, Lincoln Parish, LA, Madison 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, Winn Parish, LA, Warren County, MS, Anderson County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Falls County, TX, Freestone County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Houston County, TX, Leon County, TX, Limestone County, TX, Madison County, TX, Marion County, TX, McLennan County, TX, Morris County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Robertson County, TX, Rusk County, TX, Shelby County, TX, Smith County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Shreveport radar (KSHV), 79 km from the middle of the area, began a volume at 12:19 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Tornado Watch 106Apr 12, 10:40 AM CDT

The nearest sounding before it

Shreveport, LA (KSHV), launched 12:00Z, 0.3 hours before the alert went out and 87 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: 605 J/kg
Mixed-layer CIN: -277 J/kg
Mixed-layer LCL: 681 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 255 m²/s²
0-3 km storm-relative helicity: 308 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.1

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 12, 5:52 AM CDT	Tornado Watch	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 11 more	8 hr
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, 5:44 PM CDT	Mesoscale Discussion	SPC	Madison, Tensas	91 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, 3:38 PM CDT	Mesoscale Discussion	SPC	Copiah, Covington, Jasper, Jefferson Davis, Kemper, Lauderdale and 14 more	97 min
Apr 12, 3:52 PM CDT	Mesoscale Discussion	SPC	Covington, Jefferson Davis, Jones, Marion	23 min
Apr 12, 3:53 PM CDT	Mesoscale Discussion	SPC	Greene, Perry, Wayne	97 min
Apr 12, 4:26 PM CDT	Mesoscale Discussion	SPC	Covington, Jasper, Jones	34 min
Apr 12, 4:38 PM CDT	Tornado Watch PDS	SPC	George, Greene, Perry, Stone, Wayne	7 hr
Apr 12, 4:54 PM CDT	Mesoscale Discussion	SPC	Clarke, Covington, Jasper, Jefferson Davis, Jones, Wayne	66 min
Apr 11, 7:51 PM CDT	Mesoscale Discussion	SPC	Edwards, Kinney, Real, Sutton, Uvalde, Val Verde	84 min
Apr 11, 8:37 PM CDT	Tornado Watch	SPC	Atascosa, Bandera, Bastrop, Bexar, Blanco, Caldwell and 23 more	5 hr
Apr 11, 9:23 PM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Callahan, Clay, Coke, Coleman and 23 more	67 min
Apr 11, 11:03 PM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Caldwell, Comal, DeWitt and 12 more	57 min
Apr 12, 1:37 AM CDT	Mesoscale Discussion	SPC	Bandera, Bell, Blanco, Bosque, Brazos, Brown and 44 more	113 min
Apr 12, 1:59 AM CDT	Tornado Watch	SPC	Bandera, Bastrop, Bell, Bexar, Blanco, Bosque and 37 more	6 hr
Apr 12, 4:15 AM CDT	Mesoscale Discussion	SPC	Bandera, Bastrop, Bell, Blanco, Bosque, Brown and 24 more	90 min
Apr 12, 1:10 PM CDT	Mesoscale Discussion	SPC	Camp, Collin, Cooke, Dallas, Delta, Denton and 17 more	95 min
Apr 12, 2:51 PM CDT	Severe Thunderstorm Watch	SPC	Bowie, Camp, Cass, Delta, Fannin, Franklin and 11 more	5 hr

Nearby

Mesoscale Discussions in Texas, 2020 Mesoscale Discussions in Louisiana, 2020 Mesoscale Discussions in Mississippi, 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.