Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 229

March 22, 202120 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 22, 2021, 2:51 PM CDT for 20 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Mar 22, 2021, 2:51 PM CDT (19:51 UTC)
Expired
Mar 22, 2021, 5:15 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
60%

Counties Brown County, TX, Coke County, TX, Coleman County, TX, Comanche County, TX, Concho County, TX, Crockett County, TX, Irion County, TX, Kimble County, TX, Mason County, TX, McCulloch County, TX, Menard County, TX, Mills County, TX, Reagan County, TX, Runnels County, TX, San Saba County, TX, Schleicher County, TX, Sterling County, TX, Sutton County, TX, Terrell County, TX, Tom Green County, TX

The radar

The San Angelo radar (KSJT), 41 km from the middle of the area, began a volume at 19:54 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 7.9 hours before the alert went out and 158 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 12:00Z on 2021-03-22Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Midland Regional, TX at 12:00Z on 2021-03-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 67 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2018 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
67 m²/s²
0-3 km storm-relative helicity
60 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

303 
ACUS11 KWNS 221951
SWOMCD
SPC MCD 221951 
TXZ000-222215-

Mesoscale Discussion 0229
NWS Storm Prediction Center Norman OK
0251 PM CDT Mon Mar 22 2021

Areas affected...Southwest TX/Edwards Plateau

Concerning...Severe potential...Watch possible 

Valid 221951Z - 222215Z

Probability of Watch Issuance...60 percent

SUMMARY...Occasionally strong to severe thunderstorms are possible
this afternoon into this evening. Hail and damaging wind gusts are
the primary threats and trends are being monitored for possible
watch issuance.

DISCUSSION...Recent surface analysis places a low over the central
TX South Plains (northwest of BGS) with a dryline extending
southwestward from this low into the TX Big Bend area. A arcing band
of deeper convection notable on radar and satellite preceding this
dryline. This band is likely associated with the leading edge of
stronger ascent tied to the shortwave trough pushing across the
southern High Plains. 

Additional thunderstorms appear possible both along this area of
lift as well as farther back along the dryline, particularly if
clearing can be maintained in the wake of the leading ascent.
Relatively cool temperatures will temper overall buoyancy. However,
very strong vertical shear will likely compensate for this limited
buoyancy, with organized line segments and/or a supercell or two
possible. Hail and damaging wind gusts are the primary threats and
trends will be monitored possible watch issuance.

..Mosier/Hart.. 03/22/2021

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

ATTN...WFO...FWD...EWX...SJT...MAF...

LAT...LON   31340177 31960126 32300029 32159847 30699871 30130092
            30090185 30310242 31340177

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 22, 12:01 PM CDTMesoscale DiscussionSPCArmstrong, Borden, Briscoe, Childress, Collingsworth, Cottle and 20 more2 hr
Mar 22, 2:31 PM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Callahan, Childress, Clay, Cottle and 18 more4 hr
Mar 22, 4:24 PM CDTMesoscale DiscussionSPCBailey, Cochran, Crosby, Garza, Hale, Hockley and 5 more66 min
Mar 22, 5:25 PM CDTMesoscale DiscussionSPCArcher, Baylor, Bosque, Brown, Callahan, Clay and 41 more65 min
Mar 22, 6:05 PM CDTSevere Thunderstorm WatchSPCAnderson, Bell, Blanco, Bosque, Burnet, Collin and 43 more7 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.