Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 173

March 13, 202143 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 13, 2021, 8:42 PM CST for 43 counties in Texas. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Mar 13, 2021, 8:42 PM CST (02:42 UTC)
Expired
Mar 13, 2021, 10:15 PM CST
In force
93 min
Issued by
the Storm Prediction Center
Concerning
Tornado watch 20...21
All 43 counties

Armstrong County, TX, Borden County, TX, Briscoe County, TX, Carson County, TX, Childress County, TX, Coke County, TX, Collingsworth County, TX, Cottle County, TX, Crane County, TX, Crockett County, TX, Crosby County, TX, Dickens County, TX, Donley County, TX, Fisher County, TX, Floyd County, TX, Garza County, TX, Glasscock County, TX, Gray County, TX, Hall County, TX, Hansford County, TX, Hemphill County, TX, Howard County, TX, Hutchinson County, TX, Irion County, TX, Jones County, TX, Kent County, TX, King County, TX, Lipscomb County, TX, Martin County, TX, Midland County, TX, Mitchell County, TX, Motley County, TX, Nolan County, TX, Ochiltree County, TX, Pecos County, TX, Reagan County, TX, Roberts County, TX, Scurry County, TX, Sterling County, TX, Stonewall County, TX, Terrell County, TX, Upton County, TX, Wheeler County, TX

The radar

The Lubbock radar (KLBB), 102 km from the middle of the area, began a volume at 02:44 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

Midland Regional, TX (KMAF), launched 00:00Z, 2.7 hours before the alert went out and 119 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, Midland Regional, TX at 00:00Z on 2021-03-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Midland Regional, TX at 00:00Z on 2021-03-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -33 square meters per square second.1939587897117136Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3140 m above ground
0-6 km bulk shear
93 kt
0-1 km storm-relative helicity
-33 m²/s²
0-3 km storm-relative helicity
380 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

268 
ACUS11 KWNS 140242
SWOMCD
SPC MCD 140242 
OKZ000-TXZ000-140415-

Mesoscale Discussion 0173
NWS Storm Prediction Center Norman OK
0842 PM CST Sat Mar 13 2021

Areas affected...TX Panhandle...West TX

Concerning...Tornado Watch 20...21...

Valid 140242Z - 140415Z

The severe weather threat for Tornado Watch 20, 21 continues.

SUMMARY...Severe threat appears to be waning a bit across the
southern High Plains.

DISCUSSION...While large-scale forcing is now overspreading the back
edge of convection across the southern High Plains, loss of daytime
heating and the decoupling of the boundary layer appear to be
limiting updraft strength at this time. Additionally, OUN/FWD
exhibited a very strong cap near 700mb suggesting updrafts will
struggle with eastward extent. Recent radar trends support a gradual
weakening and current thinking is a new watch will not be warranted.

..Darrow.. 03/14/2021

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

ATTN...WFO...OUN...EWX...SJT...LUB...AMA...MAF...

LAT...LON   30160348 33020147 33010173 36310144 36309983 33030019
            33029956 30180163 30160348

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 13, 6:21 PM CSTMesoscale DiscussionSPCBorden, Coke, Crane, Crockett, Fisher, Glasscock and 13 more114 min

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.