Alert archive / Oklahoma / Tornado Watches in 2002

Tornado Watch 261

May 8, 200223 counties in Oklahoma

The Storm Prediction Center issued this tornado watch at May 8, 2002, 9:00 PM CDT for 23 counties in Oklahoma. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
May 8, 2002, 9:00 PM CDT (02:00 UTC)
Expired
May 9, 2002, 2:00 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
All 23 counties

Adair County, OK, Alfalfa County, OK, Blaine County, OK, Cherokee County, OK, Craig County, OK, Creek County, OK, Delaware County, OK, Garfield County, OK, Grant County, OK, Kay County, OK, Kingfisher County, OK, Logan County, OK, Mayes County, OK, Noble County, OK, Nowata County, OK, Osage County, OK, Ottawa County, OK, Pawnee County, OK, Payne County, OK, Rogers County, OK, Tulsa County, OK, Wagoner County, OK, Washington County, OK

The radar

The Vance AFB radar (KVNX), 110 km from the middle of the area, began a volume at 01:59 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.

Warnings issued inside it

24 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 8, 9:00 PM CDTSevere Thunderstorm WarningOUNGrant, Kay45 min
May 8, 9:29 PM CDTSevere Thunderstorm WarningOUNGarfield, Noble46 min
May 8, 9:33 PM CDTSevere Thunderstorm WarningTSAOsage57 min
May 8, 9:45 PM CDTSevere Thunderstorm WarningOUNKay45 min
May 8, 10:04 PM CDTSevere Thunderstorm WarningTSAPawnee56 min
May 8, 10:09 PM CDTSevere Thunderstorm WarningOUNKingfisher36 min
May 8, 10:16 PM CDTSevere Thunderstorm WarningOUNGarfield, Noble44 min
May 8, 10:26 PM CDTSevere Thunderstorm WarningTSAOsage64 min
May 8, 10:56 PM CDTSevere Thunderstorm WarningOUNBlaine49 min
May 8, 11:00 PM CDTSevere Thunderstorm WarningTSAPawnee60 min
May 8, 11:15 PM CDTFlash Flood WarningTSAOsage4 hr
May 8, 11:23 PM CDTSevere Thunderstorm WarningTSAWashington52 min
May 8, 11:27 PM CDTSevere Thunderstorm WarningTSAOsage93 min
May 8, 11:40 PM CDTSevere Thunderstorm WarningTSAAdair, Delaware65 min
May 8, 11:50 PM CDTSevere Thunderstorm WarningTSARogers55 min
May 8, 11:58 PM CDTSevere Thunderstorm WarningOUNKingfisher, Logan47 min
May 9, 12:00 AM CDTSevere Thunderstorm WarningTSANowata60 min
May 9, 12:14 AM CDTSevere Thunderstorm WarningTSAWashington46 min
May 9, 12:20 AM CDTSevere Thunderstorm WarningTSACraig55 min
May 9, 12:29 AM CDTSevere Thunderstorm WarningTSATulsa61 min
May 9, 12:32 AM CDTSevere Thunderstorm WarningTSAOsage43 min
May 9, 12:44 AM CDTSevere Thunderstorm WarningTSAAdair, Creek61 min
May 9, 1:06 AM CDTSevere Thunderstorm WarningTSARogers54 min
May 9, 1:30 AM CDTSevere Thunderstorm WarningTSAOkmulgee, Tulsa, Wagoner45 min

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 2.0 hours before the alert went out and 147 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 2002-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3758 joules per kilogram.LCLLFCEL10008507005003002001001 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 2002-05-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 232 square meters per square second.1939587897117Sfc1 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
3758 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
901 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
232 m²/s²
0-3 km storm-relative helicity
265 m²/s²
Significant tornado parameter
5.8
Supercell composite
21.5

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 090135
SEL1  
SPC WW 090130
OKZ000-090700-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 261
STORM PREDICTION CENTER NORMAN OK
830 PM CDT WED MAY 8 2002

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

   NORTHERN OKLAHOMA                           

EFFECTIVE THIS WEDNESDAY NIGHT AND THURSDAY MORNING FROM 900 PM
UNTIL 200 AM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 40 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 30 MILES WEST OF ENID OKLAHOMA TO 70 MILES
EAST NORTHEAST OF TULSA OKLAHOMA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO WATCH
NUMBER 255.  WATCH NUMBER 255 WILL NOT BE IN EFFECT AFTER 900 PM
CDT.  CONTINUE...WW 256...WW 257...WW 258...WW 259...

DISCUSSION...LINE OF SUPERCELL STORMS REMAINS ALONG THE KS/OK
BORDER.  THIS ACTIVITY WILL LIKELY PERSIST FOR SEVERAL MORE HOURS
AND TRACK EASTWARD AT ABOUT 30 KNOTS.  00Z OUN SOUNDING CONTINUES
TO INDICATE EXTREME INSTABILITY AND FAVORABLE LOW LEVEL VERTICAL
SHEAR PROFILES FOR VERY LARGE HAIL...DAMAGING WINDS...AND POSSIBLY
TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 25035.

...HART

365,0982 370,0944 360,0944 354,0982

WWUS20 KWNS 090135
SEL1  
SPC WW 090130
OKZ000-090700-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 261
STORM PREDICTION CENTER NORMAN OK
830 PM CDT WED MAY 8 2002

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

   NORTHERN OKLAHOMA                           

EFFECTIVE THIS WEDNESDAY NIGHT AND THURSDAY MORNING FROM 900 PM
UNTIL 200 AM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 40 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 30 MILES WEST OF ENID OKLAHOMA TO 70 MILES
EAST NORTHEAST OF TULSA OKLAHOMA.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...THIS TORNADO WATCH REPLACES TORNADO WATCH
NUMBER 255.  WATCH NUMBER 255 WILL NOT BE IN EFFECT AFTER 900 PM
CDT.  CONTINUE...WW 256...WW 257...WW 258...WW 259...

DISCUSSION...LINE OF SUPERCELL STORMS REMAINS ALONG THE KS/OK
BORDER.  THIS ACTIVITY WILL LIKELY PERSIST FOR SEVERAL MORE HOURS
AND TRACK EASTWARD AT ABOUT 30 KNOTS.  00Z OUN SOUNDING CONTINUES
TO INDICATE EXTREME INSTABILITY AND FAVORABLE LOW LEVEL VERTICAL
SHEAR PROFILES FOR VERY LARGE HAIL...DAMAGING WINDS...AND POSSIBLY
TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. 
MEAN STORM MOTION VECTOR 25035.

...HART

365,0982 370,0944 360,0944 354,0982

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 8, 8:00 PM CDTSevere Thunderstorm WatchSPCOttawa6 hr
May 9, 1:15 AM CDTSevere Thunderstorm WatchSPCAdair, Cherokee, Coal, Creek, Haskell, Hughes and 10 more5 hr

Nearby

Tornado Watches in Oklahoma, 2002Every tornado watch in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.