Alert archive / South Dakota / Tornado Watches in 1997

Tornado Watch 509

June 22, 1997Big Stone County, Minnesota; 20 counties in South Dakota

The Storm Prediction Center issued this tornado watch at Jun 22, 1997, 6:00 PM CDT for Big Stone County, Minnesota; 20 counties in South Dakota. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jun 22, 1997, 6:00 PM CDT (23:00 UTC)
Expired: Jun 22, 1997, 11:00 PM CDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 21 counties

Big Stone County, MN, Beadle County, SD, Brookings County, SD, Buffalo County, SD, Clark County, SD, Codington County, SD, Day County, SD, Deuel County, SD, Edmunds County, SD, Faulk County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Hyde County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Miner County, SD, Moody County, SD, Sanborn County, SD, Spink County, SD

The radar

The Aberdeen radar (KABR), 86 km from the middle of the area, began a volume at 23:01 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

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

Issued	Product	Office	Counties	Lasted
Jun 22, 6:06 PM CDT	Severe Thunderstorm Warning	ABR	Hamlin	59 min
Jun 22, 7:43 PM CDT	Severe Thunderstorm Warning	FSD	Brookings	32 min

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 11.0 hours before the alert went out and 55 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: 1357 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 762 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 79 m²/s²
0-3 km storm-relative helicity: 136 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.9

Open this sounding in Storm Lab

The text

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

984 
WWUS9 KMKC 222240
SEL9  
MKC WW 222240
SDZ000-230400-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 509
STORM PREDICTION CENTER NORMAN OK
540 PM CDT SUN JUN 22 1997

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

   EASTERN SOUTH DAKOTA                       

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 600 PM UNTIL 1100
PM CDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 80 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 85 STATUTE MILES EAST AND WEST
OF A LINE FROM 15 MILES EAST NORTHEAST OF ABERDEEN SOUTH DAKOTA TO
35 MILES SOUTH SOUTHEAST OF HURON SOUTH DAKOTA.

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 501.  WATCH NUMBER 501 WILL NOT BE IN EFFECT AFTER 600 PM
CDT.  CONTINUE...WW 503...WW 504...WW 505...WW 506...WW 507...

DISCUSSION...VERY UNSTABLE AIRMASS WITH CAPES TO 5000 J/KG REMAIN
EASTERN SD.  88D WIND PROFILES AT ABR INDCT VERY FAVORABLE SHEAR
REMAINS FOR SUPERCELL AND TORNADO DEVELOPMENT.  STORMS CONTINUE TO
DEVELOP EASTERN SD AND MOVE E/SE.


AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 70 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. 
MEAN STORM MOTION VECTOR 27030.


...HALES

452,0962 435,0961 435,0994 452,0995

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 22, 5:00 PM CDT	Tornado Watch	SPC	Brown, Chippewa, Cottonwood, Jackson, Kandiyohi, Lac qui Parle and 12 more	5 hr
Jun 22, 12:00 PM CDT	Tornado Watch	SPC	Beadle, Brookings, Brown, Buffalo, Campbell, Clark and 29 more	6 hr
Jun 22, 4:30 PM CDT	Tornado Watch	SPC	Harding, Perkins	7 hr
Jun 22, 6:00 PM CDT	Severe Thunderstorm Watch	SPC	Bennett, Butte, Custer, Fall River, Haakon, Hughes and 13 more	5 hr

Nearby

Tornado Watches in South Dakota, 1997 Tornado Watches in Minnesota, 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.