Alert archive / Texas / Mesoscale Discussions in 2020
Mesoscale Discussion 401
The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2020, 7:22 AM CDT for 58 counties in Texas. It was in force for 113 min.
The area
The outline as issued.
The facts
- Issued
- Apr 19, 2020, 7:22 AM CDT (12:22 UTC)
- Expired
- Apr 19, 2020, 9:15 AM CDT
- In force
- 113 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 95%
All 58 counties
Anderson County, TX, Angelina County, TX, Austin County, TX, Bastrop County, TX, Bell County, TX, Brazoria County, TX, Brazos County, TX, Burleson County, TX, Caldwell County, TX, Chambers County, TX, Cherokee County, TX, Colorado County, TX, Falls County, TX, Fayette County, TX, Fort Bend County, TX, Freestone County, TX, Galveston County, TX, Gonzales County, TX, Gregg County, TX, Grimes County, TX, Hardin County, TX, Harris County, TX, Harrison County, TX, Henderson County, TX, Houston County, TX, Jackson County, TX, Jasper County, TX, Lavaca County, TX, Lee County, TX, Leon County, TX, Liberty County, TX, Limestone County, TX, Madison County, TX, Matagorda County, TX, McLennan County, TX, Milam County, TX, Montgomery County, TX, Nacogdoches County, TX, Navarro County, TX, Panola County, TX, Polk County, TX, Robertson County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, San Jacinto County, TX, Shelby County, TX, Smith County, TX, Travis County, TX, Trinity County, TX, Tyler County, TX, Upshur County, TX, Van Zandt County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX, Williamson County, TX
The radar
The Houston radar (KHGX), 152 km from the middle of the area, began a volume at 12:21 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
Lake Charles Mun, LA (KLCH), launched 12:00Z, 0.4 hours before the alert went out and 241 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
- 1153 J/kg
- Mixed-layer CIN
- -291 J/kg
- Mixed-layer LCL
- 1054 m above ground
- 0-6 km bulk shear
- 54 kt
- 0-1 km storm-relative helicity
- 215 m²/s²
- 0-3 km storm-relative helicity
- 276 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 4.7
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 | Bowie, Camp, Cass, Cherokee, Delta, Franklin and 15 more | 2 hr |
| 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, 11:19 AM CDT | Mesoscale Discussion | SPC | Bowie, Camp, Cass, Collin, Dallas, Delta and 16 more | 116 min |
| 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, 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.