Alert archive / Texas / Mesoscale Discussions in 2021
Mesoscale Discussion 770
The Storm Prediction Center issued this mesoscale discussion at May 27, 2021, 2:50 PM CDT for 40 counties in Texas. It was in force for 115 min.
The area
The outline as issued.
The facts
- Issued
- May 27, 2021, 2:50 PM CDT (19:50 UTC)
- Expired
- May 27, 2021, 4:45 PM CDT
- In force
- 115 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch likely
- Chance of a watch
- 80%
All 40 counties
Borden County, TX, Childress County, TX, Coke County, TX, Collingsworth County, TX, Cottle County, TX, Crane County, TX, Crockett County, TX, Crosby County, TX, Dickens County, TX, Donley County, TX, Ector County, TX, Fisher County, TX, Foard County, TX, Garza County, TX, Glasscock County, TX, Hall County, TX, Haskell County, TX, Howard County, TX, Irion County, TX, Jones County, TX, Kent County, TX, King County, TX, Knox County, TX, Martin County, TX, Midland County, TX, Mitchell County, TX, Motley County, TX, Nolan County, TX, Pecos County, TX, Reagan County, TX, Runnels County, TX, Scurry County, TX, Shackelford County, TX, Sterling County, TX, Stonewall County, TX, Taylor County, TX, Terrell County, TX, Tom Green County, TX, Upton County, TX, Wheeler County, TX
The radar
The Midland/Odessa radar (KMAF), 109 km from the middle of the area, began a volume at 19:50 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, 7.8 hours before the alert went out and 109 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
- 1927 J/kg
- Mixed-layer CIN
- -261 J/kg
- Mixed-layer LCL
- 1145 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 246 m²/s²
- 0-3 km storm-relative helicity
- 245 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
The text
As transmitted.
334
ACUS11 KWNS 271951
SWOMCD
SPC MCD 271950
TXZ000-OKZ000-272145-
Mesoscale Discussion 0770
NWS Storm Prediction Center Norman OK
0250 PM CDT Thu May 27 2021
Areas affected...west Texas
Concerning...Severe potential...Watch likely
Valid 271950Z - 272145Z
Probability of Watch Issuance...80 percent
SUMMARY...Isolated to widely scattered thunderstorms are expected to
develop across west Texas by 22Z. Large to very large hail and
isolated damaging winds will be the main threats.
DISCUSSION...The atmosphere continues to destabilize across western
TX with steep lapse rates and dewpoints in the 60s F supporting
strong instability with MLCAPE from 3000-3500 J/kg. Storms are
already in the process of developing over the Davis mountains of
southwest TX. Additional storms will initiate along the dryline
through western TX and also along the southeast-advancing cold front
across the southeast TX Panhandle. Effective bulk shear from 40-45
kt will support supercells with large to very large hail and
downburst winds the primary threats. A couple of tornadoes cannot be
ruled out, but relatively small low-level hodographs should remain a
limiting factor for a more robust tornado threat.
..Dial/Hart.. 05/27/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OUN...EWX...SJT...LUB...AMA...MAF...
LAT...LON 30550370 31350306 32520193 34090105 35170090 35670005
34569992 32719921 29970123 30550370SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 26, 7:32 PM CDT | Mesoscale Discussion | SPC | Armstrong, Briscoe, Carson, Collingsworth, Donley, Floyd and 10 more | 88 min |
| May 26, 11:26 PM CDT | Mesoscale Discussion | SPC | Armstrong, Briscoe, Childress, Collingsworth, Cottle, Donley and 11 more | 64 min |
| May 27, 11:29 AM CDT | Mesoscale Discussion | SPC | Collingsworth, Hemphill, Wheeler | 61 min |
| May 27, 3:39 PM CDT | Severe Thunderstorm Watch | SPC | Archer, Baylor, Borden, Brewster, Briscoe, Callahan and 46 more | 7 hr |
| May 27, 6:24 PM CDT | Mesoscale Discussion | SPC | Baylor, Borden, Briscoe, Childress, Coke, Collingsworth and 33 more | 2 hr |
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.