Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 23

January 24, 20215 counties in Arkansas; 10 counties in Oklahoma; 26 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jan 24, 2021, 2:08 PM CST for 5 counties in Arkansas; 10 counties in Oklahoma; 26 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Jan 24, 2021, 2:08 PM CST (20:08 UTC)
Expired
Jan 24, 2021, 4:45 PM CST
In force
3 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch unlikely
Chance of a watch
5%
All 41 counties

Hempstead County, AR, Howard County, AR, Little River County, AR, Miller County, AR, Sevier County, AR, Atoka County, OK, Bryan County, OK, Carter County, OK, Choctaw County, OK, Jefferson County, OK, Johnston County, OK, Love County, OK, Marshall County, OK, McCurtain County, OK, Pushmataha County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Collin County, TX, Cooke County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Hopkins County, TX, Hunt County, TX, Kaufman County, TX, Lamar County, TX, Montague County, TX, Morris County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Tarrant County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wise County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 144 km from the middle of the area, began a volume at 20:12 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 12:00Z, 8.1 hours before the alert went out and 123 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 12:00Z on 2021-01-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 32 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 12:00Z on 2021-01-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 245 square meters per square second.1939587897117Sfc1 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
32 J/kg
Mixed-layer CIN
-48 J/kg
Mixed-layer LCL
445 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
245 m²/s²
0-3 km storm-relative helicity
122 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

054 
ACUS11 KWNS 242009
SWOMCD
SPC MCD 242008 
ARZ000-LAZ000-TXZ000-OKZ000-242245-

Mesoscale Discussion 0023
NWS Storm Prediction Center Norman OK
0208 PM CST Sun Jan 24 2021

Areas affected...northern Texas...far southern Oklahoma and
southwest Arkansas

Concerning...Severe potential...Watch unlikely 

Valid 242008Z - 242245Z

Probability of Watch Issuance...5 percent

SUMMARY...A storm or two may produce marginally severe hail later
today, mainly over northeast Texas.

DISCUSSION...A diffuse warm front currently exists over north TX and
into northern LA, with warm advection occurring just off the surface
ahead of the upper trough. This is occurring beneath modestly steep
midlevel lapse rates, with plenty of strong southwest flow aloft to
elongate hodographs.

Warm air advection and lift will increase along the Red River
through 00Z with 850 mb winds increasing to over 30 kt. Forecast
soundings show the increasing theta-e around 850 mb will lead to
better instability, although still not particularly strong. Given
the strong winds aloft and deep layer shear, a few of the storms
that form this afternoon may eventually consolidate into marginally
severe hail cores.

..Jewell/Hart.. 01/24/2021

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

ATTN...WFO...LZK...SHV...TSA...FWD...OUN...

LAT...LON   34329746 34609524 34119371 33669363 32939403 32489516
            32489698 32589732 33119785 33679824 34079809 34329746

Nearby

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