Alert archive / South Dakota / Tornado Watches in 1997

Tornado Watch 654

July 25, 199723 counties in South Dakota

The Storm Prediction Center issued this tornado watch at Jul 25, 1997, 6:00 PM CDT for 23 counties in South Dakota. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Jul 25, 1997, 6:00 PM CDT (23:00 UTC)
Expired: Jul 25, 1997, 11:00 PM CDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 23 counties

Beadle County, SD, Brookings County, SD, Brown County, SD, Campbell 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, Hughes County, SD, Hyde County, SD, Kingsbury County, SD, Marshall County, SD, McPherson County, SD, Potter County, SD, Roberts County, SD, Spink County, SD, Sully County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 80 km from the middle of the area, began a volume at 23:02 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

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

Issued	Product	Office	Counties	Lasted
Jul 25, 6:36 PM CDT	Severe Thunderstorm Warning	ABR	Edmunds	64 min
Jul 25, 6:45 PM CDT	Tornado Warning	ABR	Edmunds	50 min
Jul 25, 6:56 PM CDT	Tornado Warning	ABR	Brown	34 min
Jul 25, 7:15 PM CDT	Tornado Warning	ABR	Marshall	50 min
Jul 25, 7:31 PM CDT	Tornado Warning	ABR	Brown, Spink	49 min
Jul 25, 8:21 PM CDT	Severe Thunderstorm Warning	ABR	Spink	59 min
Jul 25, 8:26 PM CDT	Tornado Warning	ABR	Spink	64 min
Jul 25, 8:43 PM CDT	Severe Thunderstorm Warning	ABR	Clark	62 min
Jul 25, 8:52 PM CDT	Severe Thunderstorm Warning	ABR	Potter	63 min
Jul 25, 9:43 PM CDT	Severe Thunderstorm Warning	ABR	Hamlin	47 min
Jul 25, 9:54 PM CDT	Severe Thunderstorm Warning	FSD	Kingsbury	46 min
Jul 25, 10:13 PM CDT	Severe Thunderstorm Warning	FSD	Kingsbury	47 min
Jul 25, 10:45 PM CDT	Severe Thunderstorm Warning	FSD	Brookings	50 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: 764 J/kg
Mixed-layer CIN: -172 J/kg
Mixed-layer LCL: 926 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: -21 m²/s²
0-3 km storm-relative helicity: 2 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.6

Open this sounding in Storm Lab

The text

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

027 
WWUS9 KMKC 252240
SEL4  
MKC WW 252240
SDZ000-260400-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 654
STORM PREDICTION CENTER NORMAN OK
540 PM CDT FRI JUL 25 1997

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

   NORTHERN AND EASTERN SOUTH DAKOTA                       

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 600 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 100 STATUTE MILES EITHER SIDE
OF A LINE FROM 25 MILES WEST SOUTHWEST OF HURON SOUTH DAKOTA TO 35
MILES NORTH NORTHWEST OF ABERDEEN 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...  CONTINUE...WW 652...WW 653...

DISCUSSION...SUPERCELL STORM OVER NE SD HAS BEGUN TO TURN TO THE
RIGHT AND IS EXPECTED TO MOVE ALONG OUTFLOW BOUNDARY. DEVIANT STORM
MOTION IS PROVIDING FAVORABLE STORM RELATIVE FLOW FOR TORNADOES.


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
550.  MEAN STORM MOTION VECTOR 28025.


...VESCIO

441,1004 455,1004 455,0963 441,0964

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 24, 7:45 PM CDT	Severe Thunderstorm Watch	SPC	Aurora, Bennett, Brule, Buffalo, Charles Mix, Gregory and 12 more	5 hr
Jul 24, 10:00 PM CDT	Severe Thunderstorm Watch	SPC	Aurora, Beadle, Bon Homme, Brookings, Clark, Clay and 19 more	6 hr

Nearby

Tornado Watches in South Dakota, 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.