Alert archive / Oklahoma / Tornado Warnings in 2011

Tornado Warning 20, NWS Norman, OK

April 19, 2011Atoka County, Oklahoma

NWS Norman, OK issued this tornado warning at Apr 19, 2011, 3:31 PM CDT for Atoka County, Oklahoma. It was in force for 44 min. 4 reports 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 19, 2011, 3:31 PM CDT (20:31 UTC)
Expired
Apr 19, 2011, 4:15 PM CDT
In force
44 min
Issued by
NWS Norman, OK
Area
Storm-based polygon

County Atoka County, OK

The radar

The Norman radar (KTLX), 159 km from the middle of the area, began a volume at 20:33 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

TimeReportWhereRemark
Apr 19, 3:38 PM CDTHAIL 1.75Atoka, OK
Apr 19, 3:39 PM CDTHAIL 1Stringtown, OK
Apr 19, 3:50 PM CDTHAIL 4.255 E Stringtown, OK
Apr 19, 4:20 PM CDTHAIL 1.751 S Daisy, OK

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.

IssuedProductOfficeLasted
Apr 19, 2:16 PM CDTTornado WatchSPC10 hr

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 8.5 hours before the alert went out and 162 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, Norman, OK at 12:00Z on 2011-04-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2660 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, Norman, OK at 12:00Z on 2011-04-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 558 square meters per square second.19395878Sfc1 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
2660 J/kg
Mixed-layer CIN
-211 J/kg
Mixed-layer LCL
1094 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
558 m²/s²
0-3 km storm-relative helicity
577 m²/s²
Significant tornado parameter
0.0
Supercell composite
11.5

Open this sounding in Storm Lab

The text

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

841 
WFUS54 KOUN 192031
TOROUN
OKC005-192115-
/O.NEW.KOUN.TO.W.0020.110419T2031Z-110419T2115Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
331 PM CDT TUE APR 19 2011

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL ATOKA COUNTY IN SOUTHEAST OKLAHOMA...

* UNTIL 415 PM CDT

* AT 332 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR ATOKA...MOVING
  EAST AT 35 MPH.

* LOCATIONS IN THE WARNING INCLUDE ATOKA RESERVOIR...ATOKA...DAISY...
  NORTHERN MCGEE CREEK LAKE...REDDEN AND STRINGTOWN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. LEAVE MOBILE HOMES AND VEHICLES. IF POSSIBLE...MOVE
TO A BASEMENT OR STORM SHELTER. OTHERWISE MOVE TO AN INTERIOR ROOM OR
HALLWAY ON THE LOWEST FLOOR. STAY AWAY FROM WINDOWS AND OUTSIDE
WALLS.

&&

LAT...LON 3450 9567 3450 9578 3439 9577 3432 9616
      3443 9615 3443 9614 3448 9614 3463 9588
      3460 9587 3460 9568 3457 9566 3451 9566
TIME...MOT...LOC 2032Z 252DEG 30KT 3442 9608

$$
3 follow-up statements
922 
WWUS54 KOUN 192047
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
347 PM CDT TUE APR 19 2011

OKC005-192115-
/O.CON.KOUN.TO.W.0020.000000T0000Z-110419T2115Z/
ATOKA OK-
347 PM CDT TUE APR 19 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 415 PM CDT FOR CENTRAL
ATOKA COUNTY...

AT 345 PM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 5 MILES EAST OF 
STRINGTOWN...MOVING EAST AT 40 MPH. LARGE HAIL IS ALSO LIKELY WITH 
THE STRONGEST PART OF THE STORM TRACKING FROM NEAR STRINGTOWN TO 
REDDEN.

* LOCATIONS IN THE WARNING INCLUDE ATOKA RESERVOIR...ATOKA...DAISY...
  NORTHERN MCGEE CREEK LAKE...REDDEN AND STRINGTOWN.

LAT...LON 3450 9567 3450 9578 3439 9577 3432 9616
      3443 9615 3443 9614 3448 9614 3463 9588
      3460 9587 3460 9568 3457 9566 3451 9566
TIME...MOT...LOC 2045Z 257DEG 34KT 3444 9595

$$



CJS
713 
WWUS54 KOUN 192100
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
400 PM CDT TUE APR 19 2011

OKC005-192115-
/O.CON.KOUN.TO.W.0020.000000T0000Z-110419T2115Z/
ATOKA OK-
400 PM CDT TUE APR 19 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 415 PM CDT FOR CENTRAL
ATOKA COUNTY...

AT 357 PM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 9 MILES EAST OF 
STRINGTOWN...MOVING EAST AT 30 MPH. ALTHOUGH THE CIRCULATION IN THE 
STORM HAS WEAKENED FOR THE MOMENT... IT CONTINUES TO HAVE THE 
POTENTIAL TO INTENSIFY ONCE AGAIN. THE STORM WILL HAVE LARGE HAIL TO 
AT LEAST THE SIZE OF GOLFBALLS AND WINDS TO NEAR 65 MPH.

* LOCATIONS IN THE WARNING INCLUDE ATOKA...DAISY...NORTHERN MCGEE
  CREEK LAKE...REDDEN...SOUTHERN ATOKA RESERVOIR AND STRINGTOWN.

LAT...LON 3450 9567 3450 9578 3439 9577 3433 9613
      3441 9614 3452 9605 3463 9588 3460 9587
      3460 9568 3457 9566 3451 9566
TIME...MOT...LOC 2057Z 252DEG 27KT 3447 9588

$$



CJS
222 
WWUS54 KOUN 192110
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
410 PM CDT TUE APR 19 2011

OKC005-192115-
/O.CON.KOUN.TO.W.0020.000000T0000Z-110419T2115Z/
ATOKA OK-
410 PM CDT TUE APR 19 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 415 PM CDT FOR CENTRAL
ATOKA COUNTY...

AT 410 PM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 7 MILES SOUTHWEST OF
DAISY...MOVING EAST AT 35 MPH.

* LOCATIONS IN THE WARNING INCLUDE ATOKA...DAISY...NORTHERN MCGEE
  CREEK LAKE...REDDEN...SOUTHERN ATOKA RESERVOIR AND STRINGTOWN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO A TORNADO THREAT... THIS STORM LIKELY CONTAINS
DAMAGING HAIL TO THE SIZE OF BASEBALLS OR LARGER.

&&

LAT...LON 3450 9567 3450 9578 3439 9577 3433 9613
      3441 9614 3452 9605 3463 9588 3460 9587
      3460 9568 3457 9566 3451 9566
TIME...MOT...LOC 2110Z 253DEG 29KT 3447 9580

$$


CJS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 19, 2:26 PM CDTSpecial Weather StatementOUNCoal19 min
Apr 19, 2:42 PM CDTSevere Thunderstorm WarningOUNCoal, Hughes48 min
Apr 19, 2:56 PM CDTSpecial Weather StatementOUNMarshall19 min
Apr 19, 2:59 PM CDTSevere Thunderstorm WarningOUNAtoka, Coal61 min
Apr 19, 3:04 PM CDTSpecial Weather StatementOUNMarshall11 min
Apr 19, 3:36 PM CDTSevere Thunderstorm WarningOUNBryan54 min
Apr 19, 4:14 PM CDTSevere Thunderstorm WarningOUNAtoka33 min
Apr 19, 4:25 PM CDTSevere Thunderstorm WarningOUNBryan65 min
Apr 19, 6:45 PM CDTSpecial Weather StatementOUNRoger Mills45 min

Nearby

Tornado Warnings in Oklahoma, 2011Every tornado warning in 2011Tornadoes 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.