Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 1939

November 10, 2021Love County, Oklahoma; 15 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Nov 10, 2021, 7:48 PM CST for Love County, Oklahoma; 15 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Nov 10, 2021, 7:48 PM CST (01:48 UTC)
Expired
Nov 10, 2021, 10:45 PM CST
In force
3 hr
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 548

Counties Love County, OK, Collin County, TX, Cooke County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Fannin County, TX, Grayson County, TX, Hopkins County, TX, Hunt County, TX, Kaufman County, TX, Rains County, TX, Rockwall County, TX, Tarrant County, TX, Van Zandt County, TX, Wise County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 88 km from the middle of the area, began a volume at 01:48 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, 1.8 hours before the alert went out and 77 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°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.

786 
ACUS11 KWNS 110149
SWOMCD
SPC MCD 110148 
TXZ000-OKZ000-110445-

Mesoscale Discussion 1939
NWS Storm Prediction Center Norman OK
0748 PM CST Wed Nov 10 2021

Areas affected...north Texas

Concerning...Severe Thunderstorm Watch 548...

Valid 110148Z - 110445Z

The severe weather threat for Severe Thunderstorm Watch 548
continues.

SUMMARY...The severe hail and wind threat is expected to continue
east/southeast across the watch area.

DISCUSSION...A cluster of strong to severe storms, previously over
the Wichita Falls area, is expected to persist east/southeastward
across north TX, and possibly merge with other activity north of
Denton.  Despite loss of heating, cold air aloft with the upper
trough will overspread the moist sector where low 60s F dewpoints
remain, which will maintain favorable instability. Further, the
organized nature of the western cluster suggests several more hours
of wind and hail potential extending east/southeastward across north
TX. In addition, 0-1 km SRH of 200-300 m2/s2 may yet support a brief
tornado with cells preceding the main outflow surge.

..Jewell.. 11/11/2021

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

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

LAT...LON   32229584 32869792 34129745 33469539 32229584

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Nov 10, 11:21 PM CSTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Cherokee, Dallas and 16 more114 min

Nearby

Mesoscale Discussions in Texas, 2021Mesoscale Discussions in Oklahoma, 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.