Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 382

April 19, 20154 states

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2015, 4:45 PM CDT for 4 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 19, 2015, 4:45 PM CDT (21:45 UTC)
Expired
Apr 19, 2015, 6:45 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 107 counties

Arkansas County, AR, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Craighead County, AR, Crittenden County, AR, Cross County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Hempstead County, AR, Independence County, AR, Jackson County, AR, Jefferson County, AR, Lafayette County, AR, Lee County, AR, Lincoln County, AR, Lonoke County, AR, Miller County, AR, Monroe County, AR, Nevada County, AR, Ouachita County, AR, Phillips County, AR, Pike County, AR, Poinsett County, AR, Prairie County, AR, St. Francis County, AR, Union County, AR, White County, AR, Woodruff County, AR, Allen Parish, LA, Beauregard Parish, LA, Bienville Parish, LA, Bossier Parish, LA, Caddo Parish, LA, Calcasieu Parish, LA, Caldwell Parish, LA, Catahoula Parish, LA, Claiborne Parish, LA, De Soto Parish, LA, East Carroll 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, Rapides Parish, LA, Red River Parish, LA, Richland Parish, LA, Sabine Parish, LA, Union Parish, LA, Vernon Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Bolivar County, MS, Coahoma County, MS, Tunica County, MS, Washington County, MS, Angelina County, TX, Austin County, TX, Bastrop County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Cass County, TX, Cherokee County, TX, Colorado County, TX, Fayette County, TX, Gonzales County, TX, Gregg County, TX, Grimes County, TX, Guadalupe County, TX, Hardin County, TX, Harris County, TX, Harrison County, TX, Houston County, TX, Jasper County, TX, Jefferson County, TX, Lee County, TX, Leon County, TX, Liberty County, TX, Madison County, TX, Marion County, TX, Montgomery County, TX, Nacogdoches County, TX, Newton County, TX, Orange County, TX, Panola County, TX, Polk County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Shelby County, TX, Trinity County, TX, Tyler County, TX, Walker County, TX, Waller County, TX, Washington County, TX

The radar

The Shreveport radar (KSHV), 20 km from the middle of the area, began a volume at 21:47 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.

The nearest sounding before it

Shreveport, LA (KBAD), launched 12:00Z, 9.8 hours before the alert went out and 28 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-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 2015-04-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Shreveport, LA at 12:00Z on 2015-04-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 129 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
976 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
129 m²/s²
0-3 km storm-relative helicity
130 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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.

IssuedProductOfficeCountiesLasted
Apr 19, 12:43 PM CDTMesoscale DiscussionSPCBenton, Carroll, Clark, Crawford, Franklin, Garland and 19 more2 hr
Apr 19, 1:42 PM CDTSevere Thunderstorm WatchSPCBaxter, Benton, Boone, Carroll, Conway, Crawford and 22 more6 hr
Apr 19, 1:52 PM CDTMesoscale DiscussionSPCColumbia, Lafayette, Little River, Miller53 min
Apr 19, 2:31 PM CDTSevere Thunderstorm WatchSPCBradley, Calhoun, Clark, Cleveland, Columbia, Dallas and 10 more7 hr
Apr 19, 5:46 PM CDTTornado WatchSPCArkansas, Ashley, Bradley, Calhoun, Chicot, Clark and 36 more6 hr
Apr 19, 2:06 AM CDTMesoscale DiscussionSPCAscension, Assumption, East Baton Rouge, East Feliciana, Livingston, Orleans and 7 more84 min
Apr 19, 2:56 AM CDTMesoscale DiscussionSPCAllen, Avoyelles, Bienville, Caldwell, Catahoula, Concordia and 11 more94 min
Apr 19, 6:56 PM CDTMesoscale DiscussionSPCCameron64 min
Apr 19, 1:14 PM CDTMesoscale DiscussionSPCItawamba, Monroe, Tishomingo2 hr
Apr 18, 7:46 PM CDTMesoscale DiscussionSPCChildress, Cottle, Foard, Hardeman, Wichita, Wilbarger89 min
Apr 18, 8:24 PM CDTMesoscale DiscussionSPCAnderson, Bastrop, Bell, Blanco, Brazos, Burleson and 25 more96 min

Nearby

Mesoscale Discussions in Texas, 2015Mesoscale Discussions in Arkansas, 2015Mesoscale Discussions in Louisiana, 2015Every 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.