Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 833

June 1, 2021La Salle County, McMullen County, Webb County, Texas

The Storm Prediction Center issued this mesoscale discussion at Jun 1, 2021, 2:50 AM CDT for La Salle County, McMullen County, Webb County, Texas. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued
Jun 1, 2021, 2:50 AM CDT (07:50 UTC)
Expired
Jun 1, 2021, 4:15 AM CDT
In force
85 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 232

Counties La Salle County, TX, McMullen County, TX, Webb County, TX

The radar

The Corpus Christi radar (KCRP), 172 km from the middle of the area, began a volume at 07:49 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, 7.8 hours before the alert went out and 189 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, Corpus Christi, TX at 00:00Z on 2021-06-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 721 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, Corpus Christi, TX at 00:00Z on 2021-06-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -12 square meters per square second.193958Sfc1 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
721 J/kg
Mixed-layer CIN
-121 J/kg
Mixed-layer LCL
992 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
-12 m²/s²
0-3 km storm-relative helicity
74 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted.

830 
ACUS11 KWNS 010751
SWOMCD
SPC MCD 010750 
TXZ000-010915-

Mesoscale Discussion 0833
NWS Storm Prediction Center Norman OK
0250 AM CDT Tue Jun 01 2021

Areas affected...Portions of south TX

Concerning...Severe Thunderstorm Watch 232...

Valid 010750Z - 010915Z

The severe weather threat for Severe Thunderstorm Watch 232
continues.

SUMMARY...Isolated strong/gusty winds remain possible with a small
cluster of storms.

DISCUSSION...Strong velocities at low to mid levels have been noted
from KDFX over the past 1-2 hours with a small cluster of convection
moving slowly east-southeastward across south TX. Even though no
severe wind or damage reports have been received as of 0750Z
(Cotulla TX/KCOT recently measured a wind gust to 37 kt), isolated
strong/gusty winds will remain possible in the short term. Stronger
MLCIN likely exists to the south of this activity per recent
mesoanalysis estimates, and recent tracking of the cluster suggests
a more east-southeastward motion. The environment downstream remains
at least somewhat conducive for surface-based storms, with around
1000 J/kg of MLCAPE, 35-40 kt of deep-layer shear, and a moist
low-level airmass present. But, the lack of even more boundary-layer
instability may continue tend to limit the threat for severe wind
gusts to some extent across Severe Thunderstorm Watch 232.

..Gleason.. 06/01/2021

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

ATTN...WFO...CRP...

LAT...LON   28049967 28189932 28599919 28619834 28039831 27409881
            27349949 27689977 27779990 28049967

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 31, 7:17 PM CDTSevere Thunderstorm WatchSPCDimmit, Edwards, Kinney, Maverick, Real, Uvalde and 2 more8 hr
May 31, 10:07 PM CDTMesoscale DiscussionSPCDimmit, Maverick, Zavala83 min
Jun 1, 12:09 AM CDTSevere Thunderstorm WatchSPCBrooks, Duval, Jim Hogg, Jim Wells, La Salle, McMullen and 2 more6 hr
Jun 1, 12:44 AM CDTMesoscale DiscussionSPCDimmit, La Salle, Maverick, Zavala91 min
Jun 1, 2:14 PM CDTMesoscale DiscussionSPCDallam, Hartley2 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.