Alert archive / Oklahoma / Mesoscale Discussions in 2021

Mesoscale Discussion 1108

June 26, 202113 counties in Oklahoma; 6 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jun 26, 2021, 1:53 AM CDT for 13 counties in Oklahoma; 6 counties in Texas. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued
Jun 26, 2021, 1:53 AM CDT (06:53 UTC)
Expired
Jun 26, 2021, 3:00 AM CDT
In force
67 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 320

Counties Blaine County, OK, Caddo County, OK, Canadian County, OK, Comanche County, OK, Custer County, OK, Grady County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kingfisher County, OK, Kiowa County, OK, Tillman County, OK, Washita County, OK, Briscoe County, TX, Childress County, TX, Cottle County, TX, Hall County, TX, Hardeman County, TX, Wilbarger County, TX

The radar

The Altus AFB radar (KFDR), 85 km from the middle of the area, began a volume at 06:53 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, 6.9 hours before the alert went out and 212 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 2021-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 957 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 2021-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 295 square meters per square second.193958Sfc1 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
957 J/kg
Mixed-layer CIN
-173 J/kg
Mixed-layer LCL
1729 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
295 m²/s²
0-3 km storm-relative helicity
439 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.3

Open this sounding in Storm Lab

The text

As transmitted.

554 
ACUS11 KWNS 260654
SWOMCD
SPC MCD 260653 
OKZ000-TXZ000-260800-

Mesoscale Discussion 1108
NWS Storm Prediction Center Norman OK
0153 AM CDT Sat Jun 26 2021

Areas affected...Northwest Texas...Southwest and Central Oklahoma

Concerning...Severe Thunderstorm Watch 320...

Valid 260653Z - 260800Z

The severe weather threat for Severe Thunderstorm Watch 320
continues.

SUMMARY...An isolated wind-damage threat is expected to continue for
another one or two hours. However, the threat should be too marginal
to warrant the issuance of a new watch. If it appears the severe
threat will to linger beyond the 3 am CDT expiration of WW 320, a
local extension could be issued.

DISCUSSION...The latest high-resolution radar from Frederick,
Oklahoma and Amarillo show a broken line of strong thunderstorms
ongoing from 35 statute miles south-southwest of Amarillo arching
into the far southeast Texas Panhandle and western Oklahoma. The
storms are located along and just ahead of a cold front but behind
an outflow boundary. Surface dewpoints are in the mid to upper 60s
F. This is contributing to about 1000 J/kg of MLCAPE according to
the RAP. In addition, the WSR-88D VWP from Amarillo has 0-6 km shear
near 50 kt suggesting that a severe threat could persist for a
couple more hours. Wind damage would be the primary severe hazard.
As instability continues to weaken, the potential for wind damage
should become increasingly marginal. For this reason, new watch
issuance will not be needed beyond the 3 am CDT expiration of WW
320.

..Broyles.. 06/26/2021

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

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

LAT...LON   35619919 35049975 34650119 34360141 34160127 34060060
            33999958 34299844 34889777 35799773 36189798 36129843
            35959876 35619919

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 25, 8:49 PM CDTMesoscale DiscussionSPCBeckham, Blaine, Custer, Dewey, Greer, Harmon and 3 more86 min
Jun 25, 11:36 PM CDTMesoscale DiscussionSPCEllis, Roger Mills84 min
Jun 25, 11:42 PM CDTMesoscale DiscussionSPCCraig, Nowata, Osage, Ottawa, Washington63 min
Jun 25, 11:59 PM CDTSevere Thunderstorm WatchSPCBeckham, Blaine, Caddo, Canadian, Cleveland, Custer and 11 more5 hr
Jun 26, 12:59 PM CDTMesoscale DiscussionSPCCaddo, Canadian, Cleveland, Comanche, Cotton, Garvin and 12 more2 hr
Jun 26, 3:27 PM CDTMesoscale DiscussionSPCHarmon2 hr
Jun 26, 3:48 PM CDTSevere Thunderstorm WatchSPCCaddo, Carter, Comanche, Cotton, Garvin, Grady and 10 more9 hr
Jun 26, 6:27 PM CDTMesoscale DiscussionSPCComanche, Cotton, Grady, Jackson, Jefferson, McClain and 2 more93 min
Jun 26, 4:58 PM CDTSevere Thunderstorm WatchSPCBailey, Briscoe, Castro, Deaf Smith, Hale, Hall and 6 more8 hr

Nearby

Mesoscale Discussions in Oklahoma, 2021Mesoscale 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.