Alert archive / Texas / Tornado Watches in 2001

Tornado Watch 122

April 10, 200112 counties in Texas

The Storm Prediction Center issued this tornado watch at Apr 10, 2001, 8:45 PM CDT for 12 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Apr 10, 2001, 8:45 PM CDT (01:45 UTC)
Expired: Apr 11, 2001, 12:00 AM CDT
In force: 3 hr
Issued by: the Storm Prediction Center

Counties Coke County, TX, Crockett County, TX, Edwards County, TX, Irion County, TX, Nolan County, TX, Reagan County, TX, Schleicher County, TX, Sterling County, TX, Sutton County, TX, Tom Green County, TX, Upton County, TX, Val Verde County, TX

The radar

The San Angelo radar (KSJT), 89 km from the middle of the area, began a volume at 01:46 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.

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Apr 10, 9:49 PM CDT	Severe Thunderstorm Warning	SJT	Irion	41 min
Apr 10, 9:53 PM CDT	Severe Thunderstorm Warning	SJT	Sutton	67 min
Apr 10, 10:20 PM CDT	Tornado Warning	SJT	Sutton	40 min
Apr 10, 10:42 PM CDT	Severe Thunderstorm Warning	SJT	Irion	48 min
Apr 10, 10:52 PM CDT	Severe Thunderstorm Warning	SJT	Tom Green	38 min

The nearest sounding before it

Midland Regional, TX (KMAF), launched 00:00Z, 1.8 hours before the alert went out and 150 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: 740 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 2429 m above ground
0-6 km bulk shear: 78 kt
0-1 km storm-relative helicity: 131 m²/s²
0-3 km storm-relative helicity: 111 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.8

Open this sounding in Storm Lab

The text

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

000 
WWUS9 KMKC 110140
SEL2  

SEL2  
MKC WW 110134
TXZ000-110500-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 122
STORM PREDICTION CENTER NORMAN OK
834 PM CDT TUE APR 10 2001

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

   SOUTHWEST TEXAS                              

EFFECTIVE THIS TUESDAY NIGHT AND WEDNESDAY MORNING FROM 845 PM
UNTIL MIDNIGHT CDT.

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

THE TORNADO WATCH AREA IS ALONG AND 95 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 130 MILES SOUTHWEST OF SAN ANGELO TEXAS TO 30
MILES EAST NORTHEAST OF SAN ANGELO TEXAS.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

OTHER WATCH INFORMATION...  CONTINUE...WW 119...WW 120...WW 121...

DISCUSSION...THUNDERSTORMS FORMING ATTM OVER THE BIG BEND REGION
ARE BEING FED BY VERY MOIST /SURFACE DEWPOINTS IN THE LOW TO MID
60S/ SELY FLOW MOVING UP THE RIO GRANDE VLY.  GIVEN STRENGTH OF
SHEAR /AOA 60 KTS/ AND INCREASING LARGE SCALE ASCENT ACROSS
REGION...IT WOULD APPEAR THAT STORMS MIGHT BECOME PERSISTENT
SUPERCELLS DESPITE PRESENCE OF CAP FARTHER S AND E.  TORNADOES AND
LARGE HAIL WILL BE POSSIBLE FROM ANY SUSTAINED STORMS.  

AVIATION...TORNADOES AND 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 500. 
MEAN STORM MOTION VECTOR 23050.

...CORFIDI

;312,1020 325,1000 300,1000 283,1020;

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 10, 7:00 PM CDT	Tornado Watch	SPC	Armstrong, Borden, Briscoe, Carson, Childress, Collingsworth and 32 more	5 hr
Apr 10, 9:30 PM CDT	Tornado Watch	SPC	Archer, Baylor, Brown, Callahan, Clay, Coleman and 26 more	6 hr
Apr 11, 12:00 AM CDT	Tornado Watch	SPC	Childress, Collingsworth, Cottle, Hall, Hardeman, Hemphill and 2 more	4 hr
Apr 11, 2:45 AM CDT	Tornado Watch	SPC	Bell, Bosque, Brown, Clay, Collin, Comanche and 30 more	5 hr
Apr 11, 6:15 AM CDT	Tornado Watch	SPC	Bowie, Camp, Cass, Delta, Franklin, Gregg and 15 more	6 hr

Nearby

Tornado Watches in Texas, 2001 Every tornado watch in 2001

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.