Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 940

June 12, 2021Cimarron County, Oklahoma; 12 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jun 12, 2021, 9:23 PM CDT for Cimarron County, Oklahoma; 12 counties in Texas. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued
Jun 12, 2021, 9:23 PM CDT (02:23 UTC)
Expired
Jun 12, 2021, 10:30 PM CDT
In force
67 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
60%

Counties Cimarron County, OK, Bailey County, TX, Castro County, TX, Dallam County, TX, Deaf Smith County, TX, Hartley County, TX, Moore County, TX, Oldham County, TX, Parmer County, TX, Potter County, TX, Randall County, TX, Sherman County, TX, Swisher County, TX

The radar

The Amarillo radar (KAMA), 55 km from the middle of the area, began a volume at 02:24 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

Amarillo Airport, TX (KAMA), launched 00:00Z, 2.4 hours before the alert went out and 56 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, Amarillo Airport, TX at 00:00Z on 2021-06-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3697 joules per kilogram.LCLLFCEL10008507005003002001001 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, Amarillo Airport, TX at 00:00Z on 2021-06-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.1939Sfc1 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
3697 J/kg
Mixed-layer CIN
-21 J/kg
Mixed-layer LCL
1361 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
190 m²/s²
Significant tornado parameter
1.9
Supercell composite
18.7

Open this sounding in Storm Lab

The text

As transmitted.

754 
ACUS11 KWNS 130224
SWOMCD
SPC MCD 130223 
OKZ000-TXZ000-130330-

Mesoscale Discussion 0940
NWS Storm Prediction Center Norman OK
0923 PM CDT Sat Jun 12 2021

Areas affected...Western portions of the Oklahoma and Texas
Panhandle Region

Concerning...Severe potential...Watch possible 

Valid 130223Z - 130330Z

Probability of Watch Issuance...60 percent

SUMMARY...Severe thunderstorm watch may be warranted for western
portions of the Oklahoma and Texas Panhandle region. Damaging winds
and large hail are the primary risks.

DISCUSSION...Convection that developed off the higher terrain from
southeast CO into central NM has finally developed enough mass/cold
pool to begin propagating southeast away from the initiating
region/steeper low-level lapse rates. 00z sounding from AMA
exhibited a weak cap near 700mb, but with a 70F surface dew point
MLCAPE was ~3700 J/kg. There is some concern this activity may
spread east of ww262 as east-southeast boundary-layer inflow is
quite moist and potentially buoyant. Severe thunderstorm watch may
be warranted soon to account for this threat.

..Darrow/Dial.. 06/13/2021

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

ATTN...WFO...LUB...AMA...

LAT...LON   34040294 36870265 36340139 34160155 34040294

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 12, 9:39 PM CDTSevere Thunderstorm WatchSPCCimarron, Texas6 hr
Jun 12, 11:33 PM CDTMesoscale DiscussionSPCCimarron, Texas87 min
Jun 13, 12:53 AM CDTMesoscale DiscussionSPCHarmon, Roger Mills, Texas97 min
Jun 13, 6:31 PM CDTMesoscale DiscussionSPCBlaine, Caddo, Canadian, Carter, Comanche, Cotton and 9 more119 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.