Alert archive / Oklahoma / Tornado Warnings in 2001

Tornado Warning 40, NWS Norman, OK

May 20, 2001Coal County, Oklahoma

NWS Norman, OK issued this tornado warning at May 20, 2001, 7:17 PM CDT for Coal County, Oklahoma. It was in force for 43 min. 5 reports came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
May 20, 2001, 7:17 PM CDT (00:17 UTC)
Expired
May 20, 2001, 8:00 PM CDT
In force
43 min
Issued by
NWS Norman, OK
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Coal County, OK

What was reported inside it

TimeReportWhereRemark
May 20, 7:18 PM CDTHail 1Tupelo, OK
May 20, 7:30 PM CDTHail 1.25Lula, OK
May 20, 7:39 PM CDTHail 2.75Lula, OK
May 20, 7:39 PM CDTThunderstorm WindLula, OKEight-inch diameter tree limbs were downed.
May 20, 7:40 PM CDTTornado F0Centrahoma, OKThis brief, multiple-vortex tornado formed just west of Highway 75, approximately five miles northeast of Centrahoma. The tornado dissipated after 30 to 45 seconds and resulted in no damage.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

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

IssuedProductOfficeLasted
May 20, 3:30 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 0.3 hours before the alert went out and 116 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 00:00Z on 2001-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2068 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Norman, OK at 00:00Z on 2001-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 127 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
2068 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
1431 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
127 m²/s²
0-3 km storm-relative helicity
175 m²/s²
Significant tornado parameter
1.3
Supercell composite
13.3

Open this sounding in Storm Lab

The text

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

000 
WFUS54 KOUN 210018
TOROKC

OKC029-210100-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE NORMAN OK
717 PM CDT SUN MAY 20 2001

THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

* TORNADO WARNING FOR...
  COAL COUNTY IN SOUTHEAST OKLAHOMA

* UNTIL 800 PM CDT

* AT 717 PM CDT...A THUNDERSTORM WITH A HISTORY OF PRODUCING   
TORNADOES WAS LOCATED 4 MILES NORTHWEST OF TUPELO...MOVING EAST
AND SOUTHEAST AT 25 MPH.

* LOCATIONS IN THE WARNING INCLUDE CENTRAHOMA

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 3477 9640 3460 9651 3458 9611 3478 9609

BT

The office that day

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

IssuedProductOfficeCountiesLasted
May 20, 7:43 PM CDTTornado WarningOUNAtoka32 min
May 20, 11:38 PM CDTSevere Thunderstorm WarningOUNCoal, Hughes52 min
May 21, 12:28 AM CDTSevere Thunderstorm WarningOUNAtoka, Coal47 min

Nearby

Tornado Warnings in Oklahoma, 2001Every tornado warning in 2001Tornadoes 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.