Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 117, NWS Tulsa, OK

May 11, 2001Cherokee County, Oklahoma

NWS Tulsa, OK issued this severe thunderstorm warning at May 11, 2001, 2:35 PM CDT for Cherokee County, Oklahoma. It was in force for 40 min. 1 report 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 11, 2001, 2:35 PM CDT (19:35 UTC)
Expired
May 11, 2001, 3:15 PM CDT
In force
40 min
Issued by
NWS Tulsa, OK
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Cherokee County, OK

What was reported inside it

TimeReportWhereRemark
May 11, 2:45 PM CDTHail 1Hulbert, OKQuarter size hail fell at Sequoyah State Park.

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 nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 7.6 hours before the alert went out and 166 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, Springfield, MO at 12:00Z on 2001-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 276 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, Springfield, MO at 12:00Z on 2001-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 173 square meters per square second.193958Sfc1 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
276 J/kg
Mixed-layer CIN
-77 J/kg
Mixed-layer LCL
1033 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
173 m²/s²
0-3 km storm-relative helicity
236 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

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

000 
WUUS54 KTSA 111935
SVRTUL
OKC021-112015-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TULSA OK
235 PM CDT FRI MAY 11 2001

THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN CHEROKEE COUNTY IN EAST CENTRAL OKLAHOMA

* UNTIL 315 PM CDT

* AT 235 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 6
  MILES WEST OF HULBERT...MOVING SOUTHEAST AT 15 MPH.

* SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...HULBERT.

HAIL TO THE SIZE OF DIMES AND WIND GUSTS TO 60 MPH CAN BE EXPECTED IN
THE WARNED AREA.

LAT...LON 3605 9523 3595 9534 3583 9526 3584 9504

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at May 11, 1:25 PM CDT, 1 hour 10 minutes earlier.

Area forecast discussion, May 11, 1:25 PM CDT, 1 hour 10 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TULSA OK
125 PM CDT FRI MAY 11 2001

UPDATING THE FORECAST TO UP POPS TO LIKELY OR BETTER IN THE
NORTHWEST PART OF THE FORECAST AREA AND TO LOWER TEMPERATURES IN
ARKANSAS FOR THE REST OF THE AFTERNOON.

.TSA...
AR...NONE.
OK...NONE.

PLATE

In the hours before

Local storm report, May 11, 12:06 PM CDT, 2 hours 29 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TULSA OK
1206 PM CDT FRI MAY 11 2001

TIME(CDT)  .....CITY LOCATION..... STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

1120 AM    CENTERTON                 AR    .75 INCH HAIL
05/11/01   BENTON                          REPORTED BY SHERIFFS
                                           DEPT.
Special weather statement, May 11, 1:00 PM CDT, 1 hour 35 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-121100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT FRI MAY 11 2001

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE OVER PORTIONS OF
EASTERN OKLAHOMA AND WEST CENTRAL ARKANSAS THIS AFTERNOON...

EARLY THIS AFTERNOON...ONE AREA OF THUNDERSTORMS WAS PUSHING SLOWLY
SOUTHWARD ACROSS NORTHWEST ARKANSAS AND EAST CENTRAL OKLAHOMA...
WHILE A SECOND AREA OF THUNDERSTORMS WAS MOVING SOUTHWARD INTO NORTH
CENTRAL OKLAHOMA.  AT THE SURFACE...A COLD FRONT EXTENDED FROM
NORTHWEST OKLAHOMA INTO WESTERN MISSOURI...WHILE AN OUTFLOW BOUNDARY
EXTENDED EASTWARD ACROSS NORTH CENTRAL AND NORTHEAST OKLAHOMA AND
THEN SOUTHEAST AHEAD OF THE STORMS IN NORTHWEST ARKANSAS.

BOTH AREAS OF THUNDERSTORMS ARE EXPECTED TO CONTINUE MOVING SOUTH
ACROSS EASTERN OKLAHOMA AND WEST CENTRAL ARKANSAS THROUGH THE
AFTERNOON.  WITH SOME AFTERNOON HEATING...THE ATMOSPHERE AHEAD OF
THE STORMS WILL BECOME MORE UNSTABLE AND A FEW OF THE STORMS MAY
BRIEFLY INTENSIFY TO SEVERE LEVELS.  THE STRONGEST STORMS WILL
PRODUCE HAIL UP TO ONE INCH IN DIAMETER AND VERY ISOLATED OUTFLOW
WINDS UP TO 60 MPH.  A POTENTIALLY MORE SIGNIFICANT THREAT COULD BE
LOCALLY HEAVY RAINFALL...AS BETWEEN 1 AND 2 INCHES OF RAIN COULD
FALL THIS AFTERNOON IN A FEW ISOLATED AREAS.

THE SEVERE WEATHER THREAT WILL COME TO AN END FROM NORTH TO SOUTH
ACROSS THE AREA AND SHOULD BE ENTIRELY OUT OF THE AREA THIS EVENING.

.SPOTTER ACTIVATION...
STORM SPOTTER GROUPS AND EMERGENCY MANAGERS SHOULD MONITOR THE
LATEST FORECASTS AND UPDATES...AND BE PREPARED FOR POSSIBLE
ACTIVATION THIS AFTERNOON.

.DISCUSSION...
THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP IN THE VICINITY OF
THE OUTFLOW BOUNDARY...LIKELY FORMING A LARGE BAND OF SHOWERS AND
THUNDERSTORMS ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS BY 3 PM.
DESPITE CAPE VALUES OVER 2000 J/KG IN THE AREA AHEAD OF THE
BOUNDARY...A VERY WEAK WIND FIELD ALOFT AND THE LARGE NUMBER OF
STORMS EXPECTED WILL LIKELY PREVENT THE DEVELOPMENT OF ANY ORGANIZED
SEVERE STORMS THIS AFTERNOON.  HOWEVER...A FEW EMBEDDED
THUNDERSTORMS MAY BRIEFLY PULSE UP TO SEVERE LEVELS...BUT ANY SEVERE
WEATHER EVENT WILL BE VERY SHORT-LIVED AND ISOLATED.

GIVEN THE RELATIVELY SLOW MOTION OF THE AREA OF STORMS...SOME AREAS
MAY RECEIVE UP TO 2 INCHES OF RAINFALL.  ISOLATED RUNOFF PROBLEMS
COULD RESULT.

THREAT TABLE
VALID THROUGH 1200 UTC SATURDAY

THREAT AREA 1...SOUTHWEST OF A PONCA CITY TO TULSA TO FORT SMITH
LINE.
THUNDERSTORM PROBABILITY...90
SEVERE PROBABILITY IF STORMS OCCUR...20
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...2

THREAT AREAS DEFINE THE GREATEST RISK. PROBABILITIES ARE IN PERCENT.
SIGNIFICANT SEVERE IS DEFINED AS F1 OR GREATER WIND/TORNADO DAMAGE
AND/OR GOLFBALL SIZE HAIL OR LARGER.

A GRAPHICAL VERSION OF THIS OUTLOOK CAN BE FOUND AT:
WWW.SRH.NOAA.GOV/TULSA
Special weather statement, May 11, 1:32 PM CDT, 1 hour 3 minutes before
ARZ001-002-010-011-019-020-029-OKZ049-053>076-121100-

EASTERN OKLAHOMA/NORTHWEST ARKANSAS HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TULSA OK
100 PM CDT FRI MAY 11 2001

...ISOLATED SEVERE THUNDERSTORMS ARE POSSIBLE OVER PORTIONS OF
EASTERN OKLAHOMA AND WEST CENTRAL ARKANSAS THIS AFTERNOON...

EARLY THIS AFTERNOON...ONE AREA OF THUNDERSTORMS WAS PUSHING SLOWLY
SOUTHWARD ACROSS NORTHWEST ARKANSAS AND EAST CENTRAL OKLAHOMA...
WHILE A SECOND AREA OF THUNDERSTORMS WAS MOVING SOUTHWARD INTO NORTH
CENTRAL OKLAHOMA.  AT THE SURFACE...A COLD FRONT EXTENDED FROM
NORTHWEST OKLAHOMA INTO WESTERN MISSOURI...WHILE AN OUTFLOW BOUNDARY
EXTENDED EASTWARD ACROSS NORTH CENTRAL AND NORTHEAST OKLAHOMA AND
THEN SOUTHEAST AHEAD OF THE STORMS IN NORTHWEST ARKANSAS.

BOTH AREAS OF THUNDERSTORMS ARE EXPECTED TO CONTINUE MOVING SOUTH
ACROSS EASTERN OKLAHOMA AND WEST CENTRAL ARKANSAS THROUGH THE
AFTERNOON.  WITH SOME AFTERNOON HEATING...THE ATMOSPHERE AHEAD OF
THE STORMS WILL BECOME MORE UNSTABLE AND A FEW OF THE STORMS MAY
BRIEFLY INTENSIFY TO SEVERE LEVELS.  THE STRONGEST STORMS WILL
PRODUCE HAIL UP TO ONE INCH IN DIAMETER AND VERY ISOLATED OUTFLOW
WINDS UP TO 60 MPH.  A POTENTIALLY MORE SIGNIFICANT THREAT COULD BE
LOCALLY HEAVY RAINFALL...AS BETWEEN 1 AND 2 INCHES OF RAIN COULD
FALL THIS AFTERNOON IN A FEW ISOLATED AREAS.

THE SEVERE WEATHER THREAT WILL COME TO AN END FROM NORTH TO SOUTH
ACROSS THE AREA AND SHOULD BE ENTIRELY OUT OF THE AREA THIS EVENING.

.SPOTTER ACTIVATION...
STORM SPOTTER GROUPS AND EMERGENCY MANAGERS SHOULD MONITOR THE
LATEST FORECASTS AND UPDATES...AND BE PREPARED FOR POSSIBLE
ACTIVATION THIS AFTERNOON.

.DISCUSSION...
THUNDERSTORMS ARE EXPECTED TO CONTINUE TO DEVELOP IN THE VICINITY OF
THE OUTFLOW BOUNDARY...LIKELY FORMING A LARGE BAND OF SHOWERS AND
THUNDERSTORMS ACROSS EASTERN OKLAHOMA AND NORTHWEST ARKANSAS BY 3 PM.
DESPITE CAPE VALUES OVER 2000 J/KG IN THE AREA AHEAD OF THE
BOUNDARY...A VERY WEAK WIND FIELD ALOFT AND THE LARGE NUMBER OF
STORMS EXPECTED WILL LIKELY PREVENT THE DEVELOPMENT OF ANY ORGANIZED
SEVERE STORMS THIS AFTERNOON.  HOWEVER...A FEW EMBEDDED
THUNDERSTORMS MAY BRIEFLY PULSE UP TO SEVERE LEVELS...BUT ANY SEVERE
WEATHER EVENT WILL BE VERY SHORT-LIVED AND ISOLATED.

GIVEN THE RELATIVELY SLOW MOTION OF THE AREA OF STORMS...SOME AREAS
MAY RECEIVE UP TO 2 INCHES OF RAINFALL.  ISOLATED RUNOFF PROBLEMS
COULD RESULT.

THREAT TABLE
VALID THROUGH 1200 UTC SATURDAY

THREAT AREA 1...SOUTHWEST OF A PONCA CITY TO TULSA TO FORT SMITH
LINE.
THUNDERSTORM PROBABILITY...90
SEVERE PROBABILITY IF STORMS OCCUR...20
SIGNIFICANT SEVERE PROBABILITY IF STORMS OCCUR...2

THREAT AREAS DEFINE THE GREATEST RISK. PROBABILITIES ARE IN PERCENT.
SIGNIFICANT SEVERE IS DEFINED AS F1 OR GREATER WIND/TORNADO DAMAGE
AND/OR GOLFBALL SIZE HAIL OR LARGER.

A GRAPH
ICAL VERSION OF THIS OUTLOOK CAN BE FOUND AT:
WWW.SRH.NOAA.GOV/TULSA

The office that day

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

IssuedProductOfficeCountiesLasted
May 11, 1:41 PM CDTSevere Thunderstorm WarningTSACreek, Tulsa49 min
May 11, 3:19 PM CDTSevere Thunderstorm WarningTSAHaskell41 min
May 11, 4:05 PM CDTSevere Thunderstorm WarningTSAOkmulgee, Tulsa, Wagoner40 min
May 11, 4:31 PM CDTFlash Flood WarningTSAMuskogee119 min
May 11, 4:45 PM CDTSevere Thunderstorm WarningTSAOkmulgee30 min
May 11, 4:59 PM CDTSevere Thunderstorm WarningTSAMcIntosh61 min
May 11, 5:20 PM CDTSevere Thunderstorm WarningTSAPittsburg40 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2001Every severe thunderstorm warning 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.