Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 24

January 24, 2021Jackson County, Tillman County, Oklahoma; 17 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jan 24, 2021, 6:40 PM CST for Jackson County, Tillman County, Oklahoma; 17 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jan 24, 2021, 6:40 PM CST (00:40 UTC)
Expired: Jan 24, 2021, 9:15 PM CST
In force: 3 hr
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch possible
Chance of a watch: 40%

Counties Jackson County, OK, Tillman County, OK, Borden County, TX, Childress County, TX, Cottle County, TX, Crosby County, TX, Dickens County, TX, Floyd County, TX, Foard County, TX, Garza County, TX, Hardeman County, TX, Kent County, TX, King County, TX, Knox County, TX, Lubbock County, TX, Lynn County, TX, Motley County, TX, Stonewall County, TX, Wilbarger County, TX

The radar

The Lubbock radar (KLBB), 103 km from the middle of the area, began a volume at 00:42 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

Amarillo Airport, TX (KAMA), launched 00:00Z, 0.7 hours before the alert went out and 192 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 581 m above ground
0-6 km bulk shear: 101 kt
0-1 km storm-relative helicity: 271 m²/s²
0-3 km storm-relative helicity: 268 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

567 
ACUS11 KWNS 250040
SWOMCD
SPC MCD 250040 
OKZ000-TXZ000-250315-

Mesoscale Discussion 0024
NWS Storm Prediction Center Norman OK
0640 PM CST Sun Jan 24 2021

Areas affected...TX South Plains to Southwest OK

Concerning...Severe potential...Watch possible 

Valid 250040Z - 250315Z

Probability of Watch Issuance...40 percent

SUMMARY...Thunderstorms will develop across the Texas South Plains
and spread into southwest Oklahoma by midnight. Some hail threat
will be noted with these storms.

DISCUSSION...Leading edge of large-scale forcing for ascent is
currently spreading across southeast NM and far west TX, per rapidly
expanding/thickening mid-level cloudiness. Over the last half hour
or so, a few lightning flashes have developed with deepening
convection from Yoakum county to Hockley county, just west-southwest
of Lubbock. This activity is developing north of the cold front
where low-level warm advection (atop the cooler air mass) will be
maximized over the next few hours. Earlier high-res model guidance
suggested this activity would evolve by early evening then
spread/develop northeast toward southwestern OK. Given recent
satellite/radar trends, it appears this guidance is reasonable.
Forecast soundings suggest MUCAPE will support robust updrafts and
there may be adequate instability, given the lapse rates, for severe
hail. Ample shear exists for elevated supercells but the majority of
hail may be on the order of 1 inch, or less. Some consideration will
be given for a severe thunderstorm watch along this corridor.

..Darrow/Thompson.. 01/25/2021

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

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

LAT...LON   33730230 34879946 34119853 33279980 32580183 33730230

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 25, 12:42 AM CST	Mesoscale Discussion	SPC	Atoka, Bryan, Carter, Choctaw, Cleveland, Coal and 23 more	2 hr
Jan 25, 3:30 AM CST	Mesoscale Discussion	SPC	Atoka, Bryan, Choctaw, Coal, Johnston, Love and 1 more	2 hr
Jan 25, 7:38 AM CST	Mesoscale Discussion	SPC	McCurtain	2 hr

Nearby

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