Alert archive / Oklahoma / Tornado Warnings in 2011

Tornado Warning 33, NWS Norman, OK

May 21, 2011Garvin County, McClain County, Pontotoc County, Oklahoma

NWS Norman, OK issued this tornado warning at May 21, 2011, 7:49 PM CDT for Garvin County, McClain County, Pontotoc County, Oklahoma. It was in force for 41 min. 3 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: May 21, 2011, 7:49 PM CDT (00:49 UTC)
Expired: May 21, 2011, 8:30 PM CDT
In force: 41 min
Issued by: NWS Norman, OK
Area: Storm-based polygon

Counties Garvin County, OK, McClain County, OK, Pontotoc County, OK

The radar

The Norman radar (KTLX), 68 km from the middle of the area, began a volume at 00:52 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
May 21, 8:19 PM CDT	TORNADO	2 Nw Vanoss, OK
May 21, 8:30 PM CDT	TORNADO	8 W Ada, OK
May 21, 8:34 PM CDT	TORNADO	5 W Ada, 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.

Issued	Product	Office	Lasted
May 21, 7:08 PM CDT	Tornado Watch	SPC	3 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 0.8 hours before the alert went out and 66 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: 1388 J/kg
Mixed-layer CIN: -20 J/kg
Mixed-layer LCL: 2020 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 144 m²/s²
0-3 km storm-relative helicity: 205 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.5

Open this sounding in Storm Lab

The text

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

140 
WFUS54 KOUN 220049
TOROUN
OKC049-087-123-220130-
/O.NEW.KOUN.TO.W.0033.110522T0049Z-110522T0130Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
749 PM CDT SAT MAY 21 2011

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
  EXTREME SOUTHEASTERN MCCLAIN COUNTY IN CENTRAL OKLAHOMA...
  NORTHWESTERN PONTOTOC COUNTY IN EAST CENTRAL OKLAHOMA...
  NORTHEASTERN GARVIN COUNTY IN SOUTHERN OKLAHOMA...

* UNTIL 830 PM CDT

* AT 750 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
  THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR STRATFORD...MOVING
  NORTHEAST AT 20 MPH.

* LOCATIONS IN THE WARNING INCLUDE STRATFORD AND VANOSS.

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.

A TORNADO MAY FORM AT ANYTIME. TAKE COVER NOW. ABANDON 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.

&&

LAT...LON 3477 9672 3473 9703 3486 9710 3494 9680
      3491 9678 3490 9676
TIME...MOT...LOC 0050Z 238DEG 18KT 3481 9697

$$
WR

3 follow-up statements

753 
WWUS54 KOUN 220055
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
755 PM CDT SAT MAY 21 2011

OKC049-087-123-220130-
/O.CON.KOUN.TO.W.0033.000000T0000Z-110522T0130Z/
MCCLAIN OK-GARVIN OK-PONTOTOC OK-
755 PM CDT SAT MAY 21 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
NORTHWESTERN PONTOTOC...NORTHEASTERN GARVIN AND EXTREME SOUTHEASTERN
MCCLAIN COUNTIES...

AT 755 PM CDT...A TORNADO WAS DETECTED BY RADAR NEAR STRATFORD...
MOVING EAST AT 15 MPH.

* LOCATIONS IN THE WARNING INCLUDE STRATFORD AND VANOSS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO MAY FORM AT ANYTIME. TAKE COVER NOW. ABANDON 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.

&&

LAT...LON 3477 9672 3473 9703 3486 9710 3494 9680
      3491 9678 3490 9676
TIME...MOT...LOC 0055Z 260DEG 14KT 3479 9698

$$
WR

786 
WWUS54 KOUN 220102
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
802 PM CDT SAT MAY 21 2011

OKC049-087-123-220130-
/O.CON.KOUN.TO.W.0033.000000T0000Z-110522T0130Z/
MCCLAIN OK-GARVIN OK-PONTOTOC OK-
802 PM CDT SAT MAY 21 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
NORTHWESTERN PONTOTOC...NORTHEASTERN GARVIN AND EXTREME SOUTHEASTERN
MCCLAIN COUNTIES...

AT 802 PM CDT...A TORNADO WAS DETECTED BY RADAR NEAR STRATFORD...
MOVING EAST AT 15 MPH.

* LOCATIONS IN THE WARNING INCLUDE STRATFORD AND VANOSS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO A TORNADO THREAT... THIS STORM LIKELY CONTAINS 
DAMAGING HAIL TO THE SIZE OF TENNIS BALLS.

A TORNADO MAY FORM AT ANYTIME. TAKE COVER NOW. ABANDON 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.

&&

LAT...LON 3477 9672 3473 9703 3487 9707 3494 9680
      3490 9676
TIME...MOT...LOC 0102Z 260DEG 14KT 3479 9695

$$
WR

498 
WWUS54 KOUN 220118 RRA
SVSOUN

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
818 PM CDT SAT MAY 21 2011

OKC087-220127-
/O.CAN.KOUN.TO.W.0033.000000T0000Z-110522T0130Z/
MCCLAIN OK-
818 PM CDT SAT MAY 21 2011

...THE TORNADO WARNING HAS BEEN CANCELLED FOR EXTREME SOUTHEASTERN
MCCLAIN COUNTY...

LAT...LON 3477 9672 3474 9698 3487 9696 3487 9693
      3491 9692 3494 9680 3490 9676
TIME...MOT...LOC 0117Z 257DEG 14KT 3480 9690

$$

OKC049-123-220130-
/O.CON.KOUN.TO.W.0033.000000T0000Z-110522T0130Z/
GARVIN OK-PONTOTOC OK-
818 PM CDT SAT MAY 21 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 830 PM CDT FOR
NORTHWESTERN PONTOTOC AND EXTREME NORTHEASTERN GARVIN COUNTIES...

AT 817 PM CDT...NATIONAL WEATHER SERVICE RADAR DETECTED A SEVERE 
THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 2 MILES EAST OF 
STRATFORD...MOVING EAST AT 15 MPH.

* LOCATIONS IN THE WARNING INCLUDE STRATFORD AND VANOSS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO A TORNADO THREAT... THIS STORM LIKELY CONTAINS 
DAMAGING HAIL TO THE SIZE OF TENNIS BALLS.

A TORNADO MAY FORM AT ANYTIME. TAKE COVER NOW. ABANDON 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.

&&

LAT...LON 3477 9672 3474 9698 3487 9696 3487 9693
      3491 9692 3494 9680 3490 9676
TIME...MOT...LOC 0117Z 257DEG 14KT 3480 9690

$$
WR

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 7:14 PM CDT	Special Weather Statement	OUN	Pottawatomie	31 min
May 21, 7:38 PM CDT	Severe Thunderstorm Warning	OUN	Garvin, McClain, Pontotoc, Pottawatomie, Seminole	52 min
May 21, 7:40 PM CDT	Tornado Warning	OUN	Johnston, Murray, Pontotoc	31 min
May 21, 8:04 PM CDT	Tornado Warning	OUN	Pontotoc	19 min
May 21, 8:24 PM CDT	Tornado Warning	OUN	Pontotoc	51 min
May 21, 9:07 PM CDT	Tornado Warning	OUN	Pontotoc, Seminole	23 min
May 21, 9:29 PM CDT	Severe Thunderstorm Warning	OUN	Hughes, Pontotoc, Seminole	11 min
May 22, 4:35 PM CDT	Special Weather Statement	OUN	Love	25 min
May 22, 4:41 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Jefferson, Love, Marshall	49 min
May 22, 5:15 PM CDT	Severe Thunderstorm Warning	OUN	Carter, Garvin, Johnston, Love, Murray	45 min
May 22, 5:51 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Garvin, Johnston, Murray, Pontotoc, Seminole	39 min
May 22, 6:27 PM CDT	Severe Thunderstorm Warning	OUN	Coal, Hughes, Pontotoc, Seminole	63 min
May 22, 6:31 PM CDT	Severe Thunderstorm Warning	OUN	Jefferson	59 min
May 22, 6:36 PM CDT	Special Weather Statement	OUN	Love	24 min
May 22, 6:55 PM CDT	Severe Thunderstorm Warning	OUN	Love, Marshall	50 min

Nearby

Tornado Warnings in Oklahoma, 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.