Alert archive / Texas / Tornado Warnings in 2011

Tornado Warning 3, NWS Midland/Odessa, TX

April 21, 2011Pecos County, Terrell County, Texas

NWS Midland/Odessa, TX issued this tornado warning at Apr 21, 2011, 5:47 PM CDT for Pecos County, Terrell County, Texas. It was in force for 58 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 21, 2011, 5:47 PM CDT (22:47 UTC)
Expired: Apr 21, 2011, 6:45 PM CDT
In force: 58 min
Issued by: NWS Midland/Odessa, TX
Area: Storm-based polygon

Counties Pecos County, TX, Terrell County, TX

The radar

The Midland/Odessa radar (KMAF), 187 km from the middle of the area, began a volume at 22:47 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 was reported inside it

Time	Report	Where	Remark
Apr 21, 6:04 PM CDT	TSTM WND GST 58	Dryden, TX	50 KNOT WIND GUST MEASURED AT DRYDEN ASOS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 21, 3:03 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Del Rio, TX (KDRT), launched 12:00Z, 10.8 hours before the alert went out and 174 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: 2808 J/kg
Mixed-layer CIN: -107 J/kg
Mixed-layer LCL: 643 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 176 m²/s²
0-3 km storm-relative helicity: 223 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 4.7

Open this sounding in Storm Lab

The text

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

546 
WFUS54 KMAF 212247
TORMAF
TXC371-443-212345-
/O.NEW.KMAF.TO.W.0003.110421T2247Z-110421T2345Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
547 PM CDT THU APR 21 2011

THE NATIONAL WEATHER SERVICE IN MIDLAND HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTH CENTRAL PECOS COUNTY IN SOUTHWEST TEXAS...
  TERRELL COUNTY IN SOUTHWEST TEXAS...

* UNTIL 645 PM CDT

* AT 543 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 16 MILES NORTH
  OF SANDERSON...MOVING SOUTHEAST AT 15 MPH.  THIS IS A DANGEROUS
  LONG LIVED STORM... PERSONS IN THE PATH OF THIS STORM SHOULD TAKE
  SHELTER.

* THE TORNADO WILL AFFECT THE FOLLOWING LOCATIONS...
  SANDERSON...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO MAY FORM AT ANY TIME... TAKE COVER NOW. ABANDON MOBILE
HOMES AND VEHICLES FOR MORE SUBSTANTIAL SHELTER. AVOID WINDOWS.

IF YOU ARE CAUGHT OUTSIDE... SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT... SEEK SHELTER IN A CULVERT... DITCH OR
LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT
THURSDAY EVENING FOR SOUTHWESTERN TEXAS.

&&

LAT...LON 3015 10188 2994 10238 3011 10265 3053 10278
      3070 10237
TIME...MOT...LOC 2246Z 323DEG 15KT 3035 10249

$$

1 follow-up statement

106 
WWUS54 KMAF 212308
SVSMAF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX
608 PM CDT THU APR 21 2011

TXC371-443-212345-
/O.CON.KMAF.TO.W.0003.000000T0000Z-110421T2345Z/
PECOS TX-TERRELL TX-
608 PM CDT THU APR 21 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM CDT FOR TERRELL
AND EXTREME SOUTH CENTRAL PECOS COUNTIES...

AT 604 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS CONTINUED TO 
DETECT A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THE 
MOST DANGEROUS PART OF THIS STORM WAS LOCATED 8 MILES NORTH 
OF SANDERSON...MOVING SOUTHEAST AT 15 MPH.

THE COMMUNITY OF SANDERSON...AND U.S. HIGHWAY 285 NORTH OF SANDERSON 
IS IN THIS PATH OF THIS STORM. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO MAY FORM AT ANY TIME...RESIDENTS ACROSS FAR SOUTHERN PECOS 
COUNTIES AND WESTERN TERRELL COUNTIES...INCLUDING THOSE IN AND NEAR 
THE COMMUNITY OF SANDERSON SHOULD TAKE COVER NOW! ABANDON MOBILE 
HOMES AND VEHICLES FOR MORE SUBSTANTIAL SHELTER. AVOID WINDOWS.

IN ADDITION TO THE TORNADO... THIS STORM IS CAPABLE OF PRODUCING
LARGE HAIL AND DESTRUCTIVE STRAIGHT LINE WINDS. SEEK SAFE SHELTER
NOW.

&&

LAT...LON 3011 10265 3033 10272 3049 10234 3015 10188
      2994 10238
TIME...MOT...LOC 2306Z 309DEG 11KT 3026 10243

$$

The office that day

Everything else NWS Midland/Odessa, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 20, 8:21 PM CDT	Severe Thunderstorm Warning	MAF	Pecos	34 min
Apr 20, 9:08 PM CDT	Severe Thunderstorm Warning	MAF	Pecos	37 min
Apr 21, 4:41 AM CDT	Red Flag Warning	MAF		40 hr
Apr 21, 5:12 AM CDT	High Wind Watch	MAF		10 hr
Apr 21, 3:29 PM CDT	Severe Thunderstorm Warning	MAF	Pecos	61 min
Apr 21, 4:18 PM CDT	Tornado Warning	MAF	Pecos, Terrell	57 min
Apr 21, 5:14 PM CDT	Tornado Warning	MAF	Pecos	61 min
Apr 21, 6:01 PM CDT	Severe Thunderstorm Warning	MAF	Scurry	14 min
Apr 21, 6:45 PM CDT	Tornado Warning	MAF	Terrell	60 min

Nearby

Tornado Warnings in Texas, 2011 Every tornado warning in 2011 Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.