Alert archive / Oklahoma / Tornado Watches in 1997

Tornado Watch 230

May 1, 19979 counties in Oklahoma

The Storm Prediction Center issued this tornado watch at May 1, 1997, 7:45 PM CDT for 9 counties in Oklahoma. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: May 1, 1997, 7:45 PM CDT (00:45 UTC)
Expired: May 1, 1997, 11:00 PM CDT
In force: 3 hr
Issued by: the Storm Prediction Center

Counties Caddo County, OK, Canadian County, OK, Comanche County, OK, Cotton County, OK, Custer County, OK, Grady County, OK, Jefferson County, OK, Stephens County, OK, Washita County, OK

The radar

The Norman radar (KTLX), 82 km from the middle of the area, began a volume at 00:48 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

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

Issued	Product	Office	Counties	Lasted
May 1, 8:20 PM CDT	Severe Thunderstorm Warning	OUN	Beckham, Custer, Washita	55 min
May 1, 8:58 PM CDT	Tornado Warning	OUN	Washita	47 min
May 1, 9:35 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Caddo, Custer	40 min
May 1, 9:35 PM CDT	Severe Thunderstorm Warning	OUN	Washita	40 min
May 1, 9:59 PM CDT	Severe Thunderstorm Warning	OUN	Canadian	61 min

The nearest sounding before it

Norman, OK (KOUN), launched 00:00Z, 0.8 hours before the alert went out and 67 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2236 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 179 m²/s²
0-3 km storm-relative helicity: 497 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

386 
WWUS9 KMKC 020026
SEL0  
MKC WW 020026
OKZ000-020400-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 230
STORM PREDICTION CENTER NORMAN OK
726 PM CDT THU MAY 1 1997

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

   CENTRAL AND SOUTHERN OKLAHOMA                           

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 745 PM UNTIL
1100 PM CDT.

TORNADOES...HAIL TO 2 1/2 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 EAST AND WEST
OF A LINE FROM 45 MILES WEST NORTHWEST OF OKLAHOMA CITY OKLAHOMA TO
45 MILES SOUTH SOUTHEAST OF FORT SILL 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.

DISCUSSION...SUPERCELL STORM CONTINUES MOVING NEARLY DUE
EAST...WELL TO THE RIGHT OF THE MEAN WIND. PERSISTENT AND STRONG
MID LEVEL ROTATION AND STORM RELATIVE HELICITY OF NEAR 700 FOR THE
OBSERVED STORM MOTION WILL MAINTAIN THREAT FOR SUPERCELLS AND ISOLD
TORNADOES FOR A FEW MORE HOURS.


AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 1/2 INCHES.  EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500.  MEAN STORM MOTION VECTOR 26525.


...VESCIO

353,0973 340,0972 340,0984 353,0990

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 1, 10:15 PM CDT	Tornado Watch	SPC	Alfalfa, Beckham, Blaine, Caddo, Canadian, Cleveland and 32 more	6 hr

Nearby

Tornado Watches in Oklahoma, 1997 Every tornado watch in 1997

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.