Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 236
The Storm Prediction Center issued this mesoscale discussion at Mar 23, 2021, 3:19 AM CDT for 26 counties in Texas. It was in force for 56 min.
The area
The outline as issued.
The facts
- Issued
- Mar 23, 2021, 3:19 AM CDT (08:19 UTC)
- Expired
- Mar 23, 2021, 4:15 AM CDT
- In force
- 56 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 46
All 26 counties
Angelina County, TX, Austin County, TX, Colorado County, TX, DeWitt County, TX, Fayette County, TX, Fort Bend County, TX, Gonzales County, TX, Grimes County, TX, Hardin County, TX, Harris County, TX, Jackson County, TX, Jasper County, TX, Karnes County, TX, Lavaca County, TX, Liberty County, TX, Montgomery County, TX, Newton County, TX, Polk County, TX, San Jacinto County, TX, Tyler County, TX, Victoria County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX, Wilson County, TX
The radar
The Houston radar (KHGX), 114 km from the middle of the area, began a volume at 08:20 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
Corpus Christi, TX (KCRP), launched 00:00Z, 8.3 hours before the alert went out and 259 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
- 59 J/kg
- Mixed-layer CIN
- -468 J/kg
- Mixed-layer LCL
- 699 m above ground
- 0-6 km bulk shear
- 69 kt
- 0-1 km storm-relative helicity
- 235 m²/s²
- 0-3 km storm-relative helicity
- 205 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
928
ACUS11 KWNS 230819
SWOMCD
SPC MCD 230819
TXZ000-230915-
Mesoscale Discussion 0236
NWS Storm Prediction Center Norman OK
0319 AM CDT Tue Mar 23 2021
Areas affected...south-central to southeast TX
Concerning...Severe Thunderstorm Watch 46...
Valid 230819Z - 230915Z
The severe weather threat for Severe Thunderstorm Watch 46
continues.
SUMMARY...A couple of strong storms may persist another hour or two,
but severe potential is quickly diminishing downstream from WW 46.
DISCUSSION...A couple of strong storms persist early this morning.
Hail and strong gusts will be possible in the short term as
convection shifts east/southeast toward the middle and upper TX
coast/Sabine Valley. However, increasing inhibition and weak
instability will largely limit severe potential downstream of WW 46
as stronger forcing lifts northeast of the region. While a couple of
strong cells may persist, the overall severe threat is quickly
diminishing and becoming more marginal/isolated in time and space. A
downstream watch is not expected.
..Leitman.. 03/23/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LCH...SHV...HGX...CRP...EWX...
LAT...LON 29399806 30379630 31149498 31419430 31199371 30859359
30569382 29979466 29069617 28739708 28699781 28749796
28849812 29079822 29399806SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 22, 8:25 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Bell, Blanco, Bosque, Brown and 53 more | 65 min |
| Mar 22, 10:21 PM CDT | Mesoscale Discussion | SPC | Bandera, Bastrop, Bell, Bexar, Blanco, Bosque and 52 more | 54 min |
| Mar 22, 10:44 PM CDT | Mesoscale Discussion | SPC | Delta, Fannin, Franklin, Hopkins, Hunt, Kaufman and 6 more | 61 min |
| Mar 22, 11:10 PM CDT | Severe Thunderstorm Watch | SPC | Austin, Bandera, Bastrop, Bexar, Blanco, Brazos and 29 more | 5 hr |
| Mar 23, 1:29 AM CDT | Mesoscale Discussion | SPC | Atascosa, Austin, Bandera, Bastrop, Bexar, Brazos and 29 more | 91 min |
Nearby
Mesoscale Discussions in Texas, 2021Every mesoscale discussion in 2021
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.