Alert archive / Texas / Mesoscale Discussions in 2021

Mesoscale Discussion 862

June 6, 202120 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jun 6, 2021, 8:49 PM CDT for 20 counties in Texas. It was in force for 116 min.

The area

The outline as issued.

The facts

Issued
Jun 6, 2021, 8:49 PM CDT (01:49 UTC)
Expired
Jun 6, 2021, 10:45 PM CDT
In force
116 min
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
40%

Counties Armstrong County, TX, Briscoe County, TX, Carson County, TX, Castro County, TX, Crosby County, TX, Dawson County, TX, Deaf Smith County, TX, Floyd County, TX, Garza County, TX, Hale County, TX, Hockley County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Moore County, TX, Oldham County, TX, Potter County, TX, Randall County, TX, Swisher County, TX, Terry County, TX

The radar

The Lubbock radar (KLBB), 90 km from the middle of the area, began a volume at 01:49 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, 1.8 hours before the alert went out and 100 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 2021-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1369 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, Amarillo Airport, TX at 00:00Z on 2021-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 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
1369 J/kg
Mixed-layer CIN
-59 J/kg
Mixed-layer LCL
2265 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
0.0
Supercell composite
11.2

Open this sounding in Storm Lab

The text

As transmitted.

660 
ACUS11 KWNS 070149
SWOMCD
SPC MCD 070149 
TXZ000-070345-

Mesoscale Discussion 0862
NWS Storm Prediction Center Norman OK
0849 PM CDT Sun Jun 06 2021

Areas affected...TX Panhandle...TX South Plains

Concerning...Severe potential...Watch possible 

Valid 070149Z - 070345Z

Probability of Watch Issuance...40 percent

SUMMARY...Thunderstorm development expected soon across the TX
Panhandle. Upscale growth into a convective line is possible, and
convective trends will be monitored closely for potential watch
issuance.

DISCUSSION...Regional radar imagery from AMA and LUB shows two
well-defined boundaries. The eastern boundary is likely associated
with low-level moisture retreating back westward across the Caprock
while the western boundary is eastward-progressing outflow
associated with the storms across the southern High Plains. This
storm outflow is relatively strong, with both CVN and CVS both
measuring 38 kt as as it moved through. Air mass over the region is
moderately unstable and only weakly capped. 00Z AMA sounding sampled
-54 J/kg of MLCIN, with mesoanalysis and forecast soundings
suggesting similar values south into the TX South Plains. Given
these thermodynamic conditions, thunderstorm development appears
likely as the two boundaries collide. Evolution of these storms
after they develop is uncertain, but one potential scenario forecast
by recent HRRR runs is for the development of an organized,
forward-propagating convective line. Given this potential and
attendant severe threat, convective trends will be monitored closely
over the next few hours.

..Mosier/Thompson.. 06/07/2021

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

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

LAT...LON   33840280 34970271 35640256 36010192 35530094 32820097
            32640261 33840280

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 6, 9:42 PM CDTSevere Thunderstorm WatchSPCArmstrong, Briscoe, Carson, Castro, Childress, Collingsworth and 22 more6 hr
Jun 6, 11:47 PM CDTMesoscale DiscussionSPCBriscoe, Cottle, Crosby, Dickens, Floyd, Garza and 8 more88 min
Jun 7, 1:37 AM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Childress, Coleman, Cottle and 20 more83 min
Jun 7, 2:48 AM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Callahan, Clay, Cooke, Denton and 17 more7 hr
Jun 7, 4:12 AM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Foard, Hardeman, Haskell and 12 more93 min
Jun 7, 7:19 AM CDTMesoscale DiscussionSPCCallahan, Comanche, Eastland, Erath, Hood, Johnson and 3 more116 min
Jun 7, 9:36 AM CDTMesoscale DiscussionSPCAnderson, Angelina, Bosque, Cherokee, Ellis, Falls and 16 more2 hr
Jun 7, 12:32 PM CDTSevere Thunderstorm WatchSPCAngelina, Bowie, Camp, Cass, Cherokee, Franklin and 24 more6 hr
Jun 7, 3:08 PM CDTMesoscale DiscussionSPCSabine, San Augustine, Shelby2 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.