Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 820

May 31, 202111 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 31, 2021, 2:12 AM CDT for 11 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
May 31, 2021, 2:12 AM CDT (07:12 UTC)
Expired
May 31, 2021, 4:45 AM CDT
In force
3 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch unlikely
Chance of a watch
5%

Counties Borden County, TX, Fisher County, TX, Haskell County, TX, Howard County, TX, Jones County, TX, Kent County, TX, Martin County, TX, Mitchell County, TX, Nolan County, TX, Scurry County, TX, Stonewall County, TX

The radar

The Lubbock radar (KLBB), 138 km from the middle of the area, began a volume at 07:15 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

Midland Regional, TX (KMAF), launched 00:00Z, 7.2 hours before the alert went out and 142 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.

Skew-T log-pSkew-T log-p diagram, Midland Regional, TX at 00:00Z on 2021-05-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 43 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Midland Regional, TX at 00:00Z on 2021-05-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -20 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
43 J/kg
Mixed-layer CIN
-343 J/kg
Mixed-layer LCL
1626 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
-20 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

868 
ACUS11 KWNS 310712
SWOMCD
SPC MCD 310712 
TXZ000-310945-

Mesoscale Discussion 0820
NWS Storm Prediction Center Norman OK
0212 AM CDT Mon May 31 2021

Areas affected...Portions of west into west-central TX

Concerning...Severe potential...Watch unlikely 

Valid 310712Z - 310945Z

Probability of Watch Issuance...5 percent

SUMMARY...Sporadic hail and strong/gusty winds will remain possible
through the early morning hours with a cluster of storms. Watch
issuance is not expected.

DISCUSSION...A small cluster of storms is ongoing as of 0710Z across
part of west TX. Recent area VWPs show 0-2 km south-southeasterly
winds around 30-40 kt transporting a low-level moisture fetch into
this convection. Even with this low-level moisture, the mid-level
lapse rates are not very steep across this region, which along with
relatively cool surface temperatures is limiting instability. Even
so, around 500-1000 J/kg of MLCAPE is present downstream into parts
of west-central TX. Modestly enhanced mid-level winds preceding an
upper trough over the Southwest are supporting deep-layer shear of
40-50 kt per latest mesoanalysis estimates, and occasional embedded
supercell structures have been noted within the line over the past
hour or so. Isolated instances of marginally severe hail appear
possible with any supercell that can be sustained. Otherwise,
sporadic strong/gusty may occur with convective downdrafts. The weak
instability should preclude a greater severe threat, and watch
issuance is not expected.

..Gleason/Grams.. 05/31/2021

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...SJT...LUB...MAF...

LAT...LON   32520220 33080116 33400066 33359943 32609960 32230025
            32070075 32060220 32520220

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 30, 8:59 PM CDTMesoscale DiscussionSPCCarson, Gray, Hansford, Hemphill, Hutchinson, Lipscomb and 6 more91 min
May 30, 9:17 PM CDTSevere Thunderstorm WatchSPCArmstrong, Carson, Collingsworth, Donley, Gray, Hemphill and 4 more5 hr
May 30, 9:22 PM CDTMesoscale DiscussionSPCAndrews, Borden, Cochran, Cottle, Crosby, Dawson and 20 more83 min
May 30, 11:43 PM CDTMesoscale DiscussionSPCBailey, Cochran, Cottle, Crosby, Dickens, Floyd and 12 more92 min
May 31, 11:33 AM CDTMesoscale DiscussionSPCAndrews, Borden, Brewster, Cochran, Crane, Crockett and 26 more87 min
May 31, 12:16 PM CDTSevere Thunderstorm WatchSPCAndrews, Coke, Crane, Crockett, Culberson, Ector and 21 more9 hr
May 31, 2:15 PM CDTMesoscale DiscussionSPCBosque, Brown, Callahan, Coleman, Comanche, Coryell and 10 more2 hr
May 31, 2:54 PM CDTSevere Thunderstorm WatchSPCBell, Bosque, Comanche, Coryell, Ellis, Erath and 13 more4 hr
May 31, 3:29 PM CDTMesoscale DiscussionSPCAndrews, Coke, Crane, Crockett, Culberson, Ector and 21 more91 min
May 31, 5:12 PM CDTMesoscale DiscussionSPCBell, Bosque, Coryell, Ellis, Falls, Freestone and 10 more93 min
May 31, 5:49 PM CDTMesoscale DiscussionSPCBrewster, Pecos, Terrell116 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.