Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 784
The Storm Prediction Center issued this mesoscale discussion at May 28, 2021, 12:49 PM CDT for 4 counties in Texas. It was in force for 86 min.
The area
The outline as issued.
The facts
- Issued
- May 28, 2021, 12:49 PM CDT (17:49 UTC)
- Expired
- May 28, 2021, 2:15 PM CDT
- In force
- 86 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 40%
Counties Brewster County, TX, Pecos County, TX, Presidio County, TX, Terrell County, TX
The radar
The Midland/Odessa radar (KMAF), 212 km from the middle of the area, began a volume at 17:50 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
Midland Regional, TX (KMAF), launched 12:00Z, 5.8 hours before the alert went out and 212 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
- 1694 J/kg
- Mixed-layer CIN
- -279 J/kg
- Mixed-layer LCL
- 1059 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- 171 m²/s²
- 0-3 km storm-relative helicity
- 164 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.2
The text
As transmitted.
275
ACUS11 KWNS 281750
SWOMCD
SPC MCD 281749
TXZ000-281915-
Mesoscale Discussion 0784
NWS Storm Prediction Center Norman OK
1249 PM CDT Fri May 28 2021
Areas affected...portions of West Texas including the Big Bend area
Concerning...Severe potential...Watch possible
Valid 281749Z - 281915Z
Probability of Watch Issuance...40 percent
SUMMARY...Storms initiating over the higher terrain of far West
Texas may require WW issuance for associated large hail/damaging
wind risk.
DISCUSSION...Latest visible satellite imagery shows cumulus growth
occurring over the Davis Mountains at this time, on the western
fringe of moisture return occurring within the easterly low-level
flow regime. With very steep lapse rates atop the moist lower
levels, and strong heating underway, an axis of mixed-layer CAPE in
excess of 3000 J/kg continues to expand westward across the Pecos
River into the Big Bend area of Texas. As such, expect at least
isolated storm development to evolve from the aforementioned cumulus
growth over the higher terrain.
With the easterly/southeasterly low-level winds veering to westerly
in excess of 30 kt in the 500 to 300 mb layer, deep-layer shear
through the cloud-bearing layer is more than sufficient -- in tandem
with the very favorable thermodynamics -- to support supercell
evolution, and attendant risk for very large hail, and locally
severe gusts. Storm coverage remains the only question at this
point, and so will continue to monitor cu field evolution and any
signs that eventual convective coverage may become sufficient to
warrant WW issuance.
..Goss/Hart.. 05/28/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...EWX...SJT...MAF...
LAT...LON 29710450 30980391 31240324 30920225 30450164 29790178
28900319 29710450SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 27, 10:24 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Clay, Haskell, Jack, Knox and 7 more | 96 min |
| May 28, 2:33 AM CDT | Mesoscale Discussion | SPC | Collin, Denton, Hunt, Rockwall, Wise | 117 min |
| May 28, 5:10 AM CDT | Mesoscale Discussion | SPC | Briscoe, Castro, Childress, Cottle, Floyd, Foard and 7 more | 2 hr |
| May 28, 11:16 AM CDT | Mesoscale Discussion | SPC | Bell, Bosque, Brazos, Brown, Burleson, Coleman and 19 more | 89 min |
| May 28, 12:14 PM CDT | Severe Thunderstorm Watch | SPC | Bell, Bosque, Brazos, Burleson, Burnet, Comanche and 22 more | 7 hr |
| May 28, 1:03 PM CDT | Mesoscale Discussion | SPC | Andrews, Bailey, Borden, Cochran, Dawson, Ector and 11 more | 57 min |
| May 28, 2:33 PM CDT | Mesoscale Discussion | SPC | Andrews, Borden, Brown, Coke, Coleman, Concho and 35 more | 117 min |
| May 28, 2:45 PM CDT | Severe Thunderstorm Watch | SPC | Brewster, Culberson, Jeff Davis, Loving, Pecos, Reeves and 3 more | 9 hr |
| May 28, 3:41 PM CDT | Severe Thunderstorm Watch | SPC | Andrews, Brown, Coke, Coleman, Concho, Crane and 20 more | 8 hr |
| May 28, 3:42 PM CDT | Mesoscale Discussion | SPC | Bell, Brazos, Brown, Burleson, Burnet, Comanche and 12 more | 93 min |
| May 28, 5:54 PM CDT | Mesoscale Discussion | SPC | Atascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 29 more | 96 min |
| May 28, 6:20 PM CDT | Severe Thunderstorm Watch | SPC | Atascosa, Austin, Bandera, Bastrop, Bexar, Blanco and 32 more | 5 hr |
| May 28, 6:49 PM CDT | Mesoscale Discussion | SPC | Bailey, Deaf Smith, Parmer | 86 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.