Alert archive / Texas / Severe Thunderstorm Watches in 2011

Severe Thunderstorm Watch 182

April 22, 201127 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Apr 22, 2011, 6:10 PM CDT for 27 counties in Texas. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 22, 2011, 6:10 PM CDT (23:10 UTC)
Expired
Apr 23, 2011, 12:00 AM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
60 kt
All 27 counties

Archer County, TX, Brown County, TX, Callahan County, TX, Clay County, TX, Coke County, TX, Coleman County, TX, Comanche County, TX, Cooke County, TX, Denton County, TX, Eastland County, TX, Erath County, TX, Grayson County, TX, Hood County, TX, Jack County, TX, Jones County, TX, Montague County, TX, Nolan County, TX, Palo Pinto County, TX, Parker County, TX, Runnels County, TX, Shackelford County, TX, Somervell County, TX, Stephens County, TX, Taylor County, TX, Throckmorton County, TX, Wise County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 93 km from the middle of the area, began a volume at 23:13 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.

What SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
20%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
50%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

6 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 22, 6:26 PM CDTSevere Thunderstorm WarningOUNArcher, Clay, Wichita64 min
Apr 22, 7:06 PM CDTSevere Thunderstorm WarningOUNClay39 min
Apr 22, 7:30 PM CDTSevere Thunderstorm WarningOUNClay, Wichita45 min
Apr 22, 7:50 PM CDTSevere Thunderstorm WarningFWDMontague55 min
Apr 22, 8:14 PM CDTSevere Thunderstorm WarningOUNClay46 min
Apr 22, 8:44 PM CDTSevere Thunderstorm WarningFWDMontague27 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 11.2 hours before the alert went out and 118 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 2011-04-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1318 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, Fort Worth, TX at 12:00Z on 2011-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 297 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
1318 J/kg
Mixed-layer CIN
-465 J/kg
Mixed-layer LCL
1244 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
297 m²/s²
0-3 km storm-relative helicity
510 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.8

Open this sounding in Storm Lab

The text

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

243 
WWUS20 KWNS 222308
SEL2
SPC WW 222308
TXZ000-230500-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 182
NWS STORM PREDICTION CENTER NORMAN OK
610 PM CDT FRI APR 22 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

       PARTS OF NORTHERN TEXAS

EFFECTIVE THIS FRIDAY NIGHT FROM 610 PM UNTIL MIDNIGHT CDT.

HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 65
STATUTE MILES EAST AND WEST OF A LINE FROM 45 MILES WEST
NORTHWEST OF SHERMAN TEXAS TO 40 MILES WEST OF BROWNWOOD TEXAS.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU2).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 179...WW 180...WW 181...

DISCUSSION...THUNDERSTORMS EXPECTED TO DEVELOP RAPIDLY ALONG THE DRY
LINE WESTERN PORTION OF THE WATCH.  WITH STRONG INSTABILITY AND
STEEP LAPSE RATES...SUPERCELLS ARE LIKELY.  WITH HIGH LCLS AND
MARGINAL LOW LEVEL SHEAR...VERY LARGE HAIL AND DAMAGING DOWNBURSTS
WINDS ARE THE PRIMARY THREAT AS STORMS MOVE EWD ACROSS THE WATCH
THRU THE EVENING.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
MOTION VECTOR 27025.


...HALES

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 21, 11:27 PM CDTMesoscale DiscussionSPCCraig, Grant, Kay, Nowata, Osage, Ottawa and 1 more3 hr
Apr 22, 10:44 AM CDTMesoscale DiscussionSPCAdair, Cherokee, Coal, Haskell, Hughes, Latimer and 5 more61 min
Apr 22, 1:23 PM CDTMesoscale DiscussionSPCAdair, Atoka, Bryan, Carter, Cherokee, Choctaw and 39 more97 min
Apr 22, 3:47 PM CDTTornado WatchSPCAdair, Atoka, Bryan, Carter, Cherokee, Choctaw and 33 more8 hr
Apr 21, 9:15 PM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Coke, Coleman, Concho and 26 more60 min
Apr 22, 5:43 PM CDTMesoscale DiscussionSPCArcher, Callahan, Clay, Coleman, Comanche, Cooke and 17 more92 min

Nearby

Severe Thunderstorm Watches in Texas, 2011Every severe thunderstorm watch 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.