Alert archive / Texas / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 252, NWS Amarillo, TX

August 21, 2018Cimarron County, Texas County, Oklahoma; Dallam County, Hansford County, Sherman County, Texas

NWS Amarillo, TX issued this severe thunderstorm warning at Aug 21, 2018, 9:41 PM CDT for Cimarron County, Texas County, Oklahoma; Dallam County, Hansford County, Sherman County, Texas. It was in force for 42 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 21, 2018, 9:41 PM CDT (02:41 UTC)
Expired: Aug 21, 2018, 10:23 PM CDT
In force: 42 min
Issued by: NWS Amarillo, TX
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Cimarron County, OK, Texas County, OK, Dallam County, TX, Hansford County, TX, Sherman County, TX

The radar

The Amarillo radar (KAMA), 143 km from the middle of the area, began a volume at 02:42 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, 2.7 hours before the alert went out and 143 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: 821 J/kg
Mixed-layer CIN: -36 J/kg
Mixed-layer LCL: 1955 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 64 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.3

Open this sounding in Storm Lab

The text

As transmitted.

722 
WUUS54 KAMA 220241
SVRAMA
OKC025-139-TXC111-195-421-220345-
/O.NEW.KAMA.SV.W.0252.180822T0241Z-180822T0345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Amarillo TX
941 PM CDT TUE AUG 21 2018

The National Weather Service in Amarillo has issued a

* Severe Thunderstorm Warning for...
  Western Texas County in the Panhandle of Oklahoma...
  Eastern Cimarron County in the Panhandle of Oklahoma...
  Sherman County in the Panhandle of Texas...
  Northwestern Hansford County in the Panhandle of Texas...
  Northeastern Dallam County in the Panhandle of Texas...

* Until 1045 PM CDT.

* At 940 PM CDT, severe thunderstorms were located along a line
  extending from near Eva to 8 miles west of Texhoma to near
  Stratford, moving east at 30 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Minor damage to roofs, siding, and trees is possible.

* Locations impacted include...
  Guymon, Stratford, Goodwell, Eva, Hough, Conlen, Griggs, Texhoma
  and Sturgis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3688 10134 3637 10142 3606 10177 3606 10195
      3631 10249 3661 10217 3696 10213
TIME...MOT...LOC 0240Z 288DEG 25KT 3683 10188 3653 10194 3630 10211 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

Rutt

2 follow-up statements

176 
WWUS54 KAMA 220309
SVSAMA

Severe Weather Statement
National Weather Service Amarillo TX
1009 PM CDT TUE AUG 21 2018

OKC025-139-TXC111-195-421-220345-
/O.CON.KAMA.SV.W.0252.000000T0000Z-180822T0345Z/
Texas OK-Cimarron OK-Sherman TX-Hansford TX-Dallam TX-
1009 PM CDT TUE AUG 21 2018

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 PM CDT
FOR WESTERN TEXAS...SOUTHEASTERN CIMARRON...SHERMAN...NORTHWESTERN
HANSFORD AND NORTHEASTERN DALLAM COUNTIES...

At 1009 PM CDT, severe thunderstorms were located along a line
extending from 8 miles southwest of Hough to 5 miles southeast of
Texhoma to 12 miles southeast of Stratford, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Minor damage to roofs, siding, and trees is possible.

Locations impacted include...
Guymon, Stratford, Goodwell, Eva, Hough, Conlen, Texhoma and Sturgis.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3688 10134 3637 10142 3606 10177 3606 10195
      3631 10249 3657 10211 3695 10204
TIME...MOT...LOC 0309Z 288DEG 25KT 3677 10165 3647 10171 3624 10188 

HAIL...<.75IN
WIND...60MPH
 
$$

Rutt

076 
WWUS54 KAMA 220323
SVSAMA

Severe Weather Statement
National Weather Service Amarillo TX
1023 PM CDT TUE AUG 21 2018

OKC025-139-TXC111-195-421-220333-
/O.CAN.KAMA.SV.W.0252.000000T0000Z-180822T0345Z/
Texas OK-Cimarron OK-Sherman TX-Hansford TX-Dallam TX-
1023 PM CDT TUE AUG 21 2018

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN TEXAS...SOUTHEASTERN
CIMARRON...SHERMAN...NORTHWESTERN HANSFORD AND NORTHEASTERN DALLAM
COUNTIES IS CANCELLED...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning has been cancelled.  However gusty winds and
heavy rain are still possible with these thunderstorms.

LAT...LON 3688 10134 3637 10142 3606 10177 3606 10195
      3631 10249 3657 10211 3695 10204
TIME...MOT...LOC 0322Z 288DEG 25KT 3674 10154 3644 10160 3621 10177 

$$

Rutt

The office that day

Everything else NWS Amarillo, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 21, 8:04 PM CDT	Special Weather Statement	AMA	Cimarron	41 min
Aug 21, 8:38 PM CDT	Areal Flood Advisory	AMA	Cimarron	3 hr
Aug 21, 8:42 PM CDT	Severe Thunderstorm Warning	AMA	Cimarron, Texas	63 min
Aug 21, 9:26 PM CDT	Areal Flood Advisory	AMA	Cimarron, Texas	3 hr
Aug 22, 8:15 AM CDT	Areal Flood Advisory	AMA	Beaver	2 hr
Aug 22, 6:32 PM CDT	Special Weather Statement	AMA	Beaver	28 min
Aug 22, 4:18 PM CDT	Special Weather Statement	AMA	Roberts	27 min
Aug 22, 4:54 PM CDT	Special Weather Statement	AMA	Roberts	36 min
Aug 22, 5:05 PM CDT	Severe Thunderstorm Warning	AMA	Roberts	55 min
Aug 22, 5:26 PM CDT	Areal Flood Advisory	AMA	Hutchinson, Roberts	114 min
Aug 22, 5:30 PM CDT	Special Weather Statement	AMA	Ochiltree	45 min

Nearby

Severe Thunderstorm Warnings in Texas, 2018 Severe Thunderstorm Warnings in Oklahoma, 2018 Every severe thunderstorm warning in 2018

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.