Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 461, NWS Norman, OK

August 19, 2021Wilbarger County, Texas; 4 counties in Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Aug 19, 2021, 6:02 PM CDT for Wilbarger County, Texas; 4 counties in Oklahoma. It was in force for 28 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 19, 2021, 6:02 PM CDT (23:02 UTC)
Expired: Aug 19, 2021, 6:30 PM CDT
In force: 28 min
Issued by: NWS Norman, OK
Area: Storm-based polygon
Damage threat: Considerable
Hail: 0.75 in
Wind: 70.0 mph

Counties Comanche County, OK, Jackson County, OK, Kiowa County, OK, Tillman County, OK, Wilbarger County, TX

The radar

The Altus AFB radar (KFDR), 32 km from the middle of the area, began a volume at 23:05 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 12:00Z, 11.0 hours before the alert went out and 235 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1123 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 988 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: 33 m²/s²
0-3 km storm-relative helicity: 89 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

675 
WUUS54 KOUN 192302
SVROUN
OKC031-065-075-141-TXC487-192330-
/O.NEW.KOUN.SV.W.0461.210819T2302Z-210819T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Norman OK
602 PM CDT Thu Aug 19 2021

The National Weather Service in Norman has issued a

* Severe Thunderstorm Warning for...
  West central Comanche County in southwestern Oklahoma...
  Central Jackson County in southwestern Oklahoma...
  South central Kiowa County in southwestern Oklahoma...
  Western Tillman County in southwestern Oklahoma...
  North central Wilbarger County in northern Texas...

* Until 630 PM CDT.

* At 602 PM CDT, a severe thunderstorm was located 5 miles south of
  Altus, moving east at 45 mph.

  HAZARD...70 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect considerable tree damage. Damage is likely to 
           mobile homes, roofs, and outbuildings.

* Locations impacted include...
  Altus, Frederick, Snyder, Tipton, Olustee, Indiahoma, Manitou,
  Elmer, Headrick, Altus Air Force Base, Humphreys and Hess.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3450 9961 3471 9945 3464 9873 3422 9899
TIME...MOT...LOC 2302Z 282DEG 41KT 3457 9933 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH

$$

WR

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 19, 4:59 PM CDT	Severe Thunderstorm Warning	OUN	Hardeman	31 min
Aug 19, 5:28 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Hardeman	47 min
Aug 19, 6:54 PM CDT	Special Weather Statement	OUN	Hardeman	36 min
Aug 19, 7:38 AM CDT	Areal Flood Advisory	OUN	Comanche	36 min
Aug 19, 8:14 AM CDT	Flash Flood Warning	OUN	Comanche	3 hr
Aug 19, 3:27 PM CDT	Special Weather Statement	OUN	Beckham	33 min
Aug 19, 3:29 PM CDT	Special Weather Statement	OUN	Harmon	31 min
Aug 19, 4:10 PM CDT	Special Weather Statement	OUN	Beckham	35 min
Aug 19, 5:14 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Greer, Harmon, Jackson	31 min
Aug 19, 6:26 PM CDT	Severe Thunderstorm Warning Considerable damage threat	OUN	Jackson, Tillman	34 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2021 Severe Thunderstorm Warnings in Texas, 2021 Every severe thunderstorm warning 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.