Alert archive / Texas / Mesoscale Discussions in 2020
Mesoscale Discussion 404
The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2020, 11:19 AM CDT for 13 counties in Arkansas; McCurtain County, Oklahoma; 22 counties in Texas. It was in force for 116 min.
The area
The outline as issued.
The facts
- Issued
- Apr 19, 2020, 11:19 AM CDT (16:19 UTC)
- Expired
- Apr 19, 2020, 1:15 PM CDT
- In force
- 116 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 36 counties
Clark County, AR, Columbia County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Pike County, AR, Polk County, AR, Sevier County, AR, Union County, AR, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Collin County, TX, Dallas County, TX, Delta County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Hopkins County, TX, Hunt County, TX, Kaufman County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX
The radar
The Shreveport radar (KSHV), 136 km from the middle of the area, began a volume at 16:18 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 12:00Z, 4.3 hours before the alert went out and 143 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.
- Mixed-layer CAPE
- 561 J/kg
- Mixed-layer CIN
- -198 J/kg
- Mixed-layer LCL
- 551 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 298 m²/s²
- 0-3 km storm-relative helicity
- 227 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 18, 8:27 PM CDT | Mesoscale Discussion | SPC | Columbia, Hempstead, Howard, Lafayette, Little River, Miller and 5 more | 2 hr |
| Apr 19, 2:34 AM CDT | Mesoscale Discussion | SPC | Arkansas, Ashley, Bradley, Chicot, Cleveland, Desha and 3 more | 116 min |
| Apr 19, 7:22 AM CDT | Mesoscale Discussion | SPC | Anderson, Angelina, Austin, Bastrop, Bell, Brazoria and 52 more | 113 min |
| Apr 19, 8:41 AM CDT | Tornado Watch | SPC | Anderson, Angelina, Austin, Brazoria, Brazos, Burleson and 38 more | 6 hr |
| Apr 19, 10:45 AM CDT | Mesoscale Discussion | SPC | Angelina, Nacogdoches, Panola, Rusk, Sabine, San Augustine and 1 more | 2 hr |
| Apr 19, 12:39 PM CDT | Mesoscale Discussion | SPC | Brazoria, Chambers, Fort Bend, Galveston, Hardin, Harris and 11 more | 66 min |
| Apr 19, 12:47 PM CDT | Mesoscale Discussion | SPC | Sabine, San Augustine | 58 min |
| Apr 19, 2:03 PM CDT | Mesoscale Discussion | SPC | Jasper, Newton, Orange, Sabine, Tyler | 57 min |
| Apr 19, 2:39 PM CDT | Tornado Watch | SPC | Angelina, Brazoria, Chambers, Fort Bend, Galveston, Hardin and 16 more | 9 hr |
Nearby
Mesoscale Discussions in Texas, 2020Mesoscale Discussions in Arkansas, 2020Mesoscale Discussions in Oklahoma, 2020Every 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.