Alert archive / Texas / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 511, NWS Norman, OK

August 12, 2011Clay County, Texas

NWS Norman, OK issued this severe thunderstorm warning at Aug 12, 2011, 4:54 PM CDT for Clay County, Texas. It was in force for 66 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 12, 2011, 4:54 PM CDT (21:54 UTC)
Expired
Aug 12, 2011, 6:00 PM CDT
In force
66 min
Issued by
NWS Norman, OK
Area
Storm-based polygon

County Clay County, TX

The radar

The Altus AFB radar (KFDR), 103 km from the middle of the area, began a volume at 21:58 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

Fort Worth, TX (KFWD), launched 12:00Z, 9.9 hours before the alert went out and 128 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, Fort Worth, TX at 12:00Z on 2011-08-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1449 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, Fort Worth, TX at 12:00Z on 2011-08-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -97 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
1449 J/kg
Mixed-layer CIN
-116 J/kg
Mixed-layer LCL
1434 m above ground
0-6 km bulk shear
2 kt
0-1 km storm-relative helicity
-97 m²/s²
0-3 km storm-relative helicity
-3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

666 
WUUS54 KOUN 122154
SVROUN
TXC077-122300-
/O.NEW.KOUN.SV.W.0511.110812T2154Z-110812T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE NORMAN OK
454 PM CDT FRI AUG 12 2011

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN CLAY COUNTY IN NORTHERN TEXAS...

* UNTIL 600 PM CDT

* AT 454 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
  THUNDERSTORM 7 MILES NORTH OF BELLEVUE...MOVING NORTH AT 5 MPH.
  ADDITIONAL SEVERE THUNDERSTORMS ARE LIKELY TO FORM SOUTH OF THE
  FIRST STORM...AFFECTING AREAS FROM BLUEGROVE TO VASHTI.

HAZARDS IN THE WARNING INCLUDE...
DAMAGING WIND GUSTS TO 65 MPH...
HAIL UP TO THE SIZE OF QUARTERS...

* LOCATIONS IN THE WARNING INCLUDE BELLEVUE...BLUEGROVE...BUFFALO
  SPRINGS...EXTREME EASTERN LAKE ARROWHEAD...HENRIETTA...JOY AND
  VASHTI.

LAT...LON 3357 9829 3369 9833 3380 9833 3386 9819
      3389 9797 3349 9798
TIME...MOT...LOC 2154Z 197DEG 6KT 3375 9801

$$

BURKE
2 follow-up statements
883 
WWUS54 KOUN 122234
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
534 PM CDT FRI AUG 12 2011

TXC077-122300-
/O.CON.KOUN.SV.W.0511.000000T0000Z-110812T2300Z/
CLAY TX-
534 PM CDT FRI AUG 12 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM CDT
FOR SOUTHERN CLAY COUNTY...

AT 534 PM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED SEVERE
THUNDERSTORMS ALONG A LINE EXTENDING FROM EASTERN LAKE ARROWHEAD TO 8
MILES NORTH OF BELLEVUE...MOVING EAST AT 5 MPH.

HAZARDS IN THE WARNING INCLUDE...
DAMAGING WIND GUSTS TO 65 MPH...
HAIL UP TO THE SIZE OF QUARTERS...

* LOCATIONS IN THE WARNING INCLUDE BELLEVUE...BLUEGROVE...BUFFALO
  SPRINGS...EXTREME EASTERN LAKE ARROWHEAD...HENRIETTA...JOY AND
  VASHTI.

LAT...LON 3357 9829 3369 9833 3380 9833 3386 9819
      3389 9797 3349 9798
TIME...MOT...LOC 2234Z 277DEG 6KT 3372 9833 3375 9800

$$

BURKE
721 
WWUS54 KOUN 122300
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
600 PM CDT FRI AUG 12 2011

TXC077-122311-
/O.EXP.KOUN.SV.W.0511.000000T0000Z-110812T2300Z/
CLAY TX-
600 PM CDT FRI AUG 12 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN CLAY COUNTY HAS
EXPIRED...

THE STORMS HAVE WEAKENED... BUT SMALL HAIL AND GUSTY WINDS MAY STILL
OCCUR.

LAT...LON 3357 9829 3369 9833 3380 9833 3386 9819
      3389 9797 3349 9798
TIME...MOT...LOC 2234Z 277DEG 6KT 3372 9833 3375 9800

$$

BURKE

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 12, 3:13 PM CDTSpecial Weather StatementOUNClay47 min
Aug 12, 3:49 PM CDTSevere Thunderstorm WarningOUNClay56 min
Aug 12, 4:49 PM CDTSpecial Weather StatementOUNClay41 min
Aug 12, 5:19 PM CDTAreal Flood AdvisoryOUNClay3 hr
Aug 12, 5:32 PM CDTSpecial Weather StatementOUNWichita43 min

Nearby

Severe Thunderstorm Warnings in Texas, 2011Every severe thunderstorm warning in 2011

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.