Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 1940

November 10, 202122 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Nov 10, 2021, 11:21 PM CST for 22 counties in Texas. It was in force for 114 min.

The area

The outline as issued.

The facts

Issued
Nov 10, 2021, 11:21 PM CST (05:21 UTC)
Expired
Nov 11, 2021, 1:15 AM CST
In force
114 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 548
All 22 counties

Anderson County, TX, Bowie County, TX, Camp County, TX, Cass County, TX, Cherokee County, TX, Dallas County, TX, Ellis County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Kaufman County, TX, Marion County, TX, Morris County, TX, Navarro County, TX, Panola County, TX, Rusk County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 158 km from the middle of the area, began a volume at 05:21 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

Fort Worth, TX (KFWD), launched 00:00Z, 5.4 hours before the alert went out and 159 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, Fort Worth, TX at 00:00Z on 2021-11-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1140 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, Fort Worth, TX at 00:00Z on 2021-11-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 238 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
1140 J/kg
Mixed-layer CIN
-16 J/kg
Mixed-layer LCL
1186 m above ground
0-6 km bulk shear
50 kt
0-1 km storm-relative helicity
238 m²/s²
0-3 km storm-relative helicity
243 m²/s²
Significant tornado parameter
1.4
Supercell composite
8.1

Open this sounding in Storm Lab

The text

As transmitted.

208 
ACUS11 KWNS 110522
SWOMCD
SPC MCD 110521 
LAZ000-ARZ000-TXZ000-110715-

Mesoscale Discussion 1940
NWS Storm Prediction Center Norman OK
1121 PM CST Wed Nov 10 2021

Areas affected...northeast Texas

Concerning...Severe Thunderstorm Watch 548...

Valid 110521Z - 110715Z

The severe weather threat for Severe Thunderstorm Watch 548
continues.

SUMMARY...Strong wind gusts remain possible across northeast Texas,
with perhaps marginal hail, but severe weather is becoming less
likely with time. Additional watches are not anticipated.

DISCUSSION...Back-building storms persist near the Dallas area,
producing heavy rain and wind gusts mainly in the 30 kt range.
Eastern portions of the line are advancing more quickly into
northeast TX, oriented a bit more orthogonal to the midlevel flow.
The area from northeast TX into northwest LA may be a favored area
for a few strong wind gusts over the next several hours. 

Overall, the severe risk appears to be dwindling, as the boundary
layer continues to stabilize. Objective analysis indicates less than
1000 J/kg MLCAPE as of 05Z, with warming midlevel temperatures out
of the southwest. Therefore, additional watches are not anticipated
tonight, though an isolated severe gust cannot be ruled out.

..Jewell.. 11/11/2021

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

ATTN...WFO...SHV...FWD...

LAT...LON   32899701 32739642 32729591 32899542 33169529 33499446
            33319411 33029392 32579393 32039415 31689476 31719553
            31919632 32219684 32459711 32709724 32899701

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 10, 7:48 PM CSTMesoscale DiscussionSPCCollin, Cooke, Dallas, Delta, Denton, Fannin and 9 more3 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.