Alert archive / South Dakota / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 656

August 30, 20029 counties in North Dakota; 12 counties in South Dakota

The Storm Prediction Center issued this severe thunderstorm watch at Aug 30, 2002, 2:35 PM CDT for 9 counties in North Dakota; 12 counties in South Dakota. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Aug 30, 2002, 2:35 PM CDT (19:35 UTC)
Expired: Aug 30, 2002, 8:00 PM CDT
In force: 5 hr
Issued by: the Storm Prediction Center

All 21 counties

Burleigh County, ND, Dunn County, ND, Emmons County, ND, Grant County, ND, McLean County, ND, Mercer County, ND, Morton County, ND, Oliver County, ND, Sioux County, ND, Campbell County, SD, Corson County, SD, Dewey County, SD, Edmunds County, SD, Faulk County, SD, Hand County, SD, Hughes County, SD, Hyde County, SD, Potter County, SD, Stanley County, SD, Sully County, SD, Walworth County, SD

Warnings issued inside it

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

Issued	Product	Office	Counties	Lasted
Aug 30, 3:11 PM CDT	Flash Flood Warning	BIS	Mercer, Oliver	3 hr
Aug 30, 5:56 PM CDT	Severe Thunderstorm Warning	BIS	Oliver	64 min
Aug 30, 6:25 PM CDT	Flash Flood Warning	BIS	McLean, Oliver	3 hr
Aug 30, 7:08 PM CDT	Severe Thunderstorm Warning	BIS	Burleigh, Morton	52 min
Aug 30, 7:24 PM CDT	Severe Thunderstorm Warning	BIS	Burleigh, McLean, Oliver, Sheridan	51 min
Aug 30, 7:46 PM CDT	Severe Thunderstorm Warning	ABR	Potter	29 min

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 7.6 hours before the alert went out and 37 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: 703 J/kg
Mixed-layer CIN: -185 J/kg
Mixed-layer LCL: 969 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 266 m²/s²
0-3 km storm-relative helicity: 198 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.2

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 301933
SEL6  
SPC WW 301935
NDZ000-SDZ000-310100-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 656
STORM PREDICTION CENTER NORMAN OK
235 PM CDT FRI AUG 30 2002

THE STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

   WESTERN NORTH DAKOTA                       
   CENTRAL SOUTH DAKOTA                       

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 235 PM UNTIL 800
PM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 60 STATUTE MILES
EAST AND WEST OF A LINE FROM 25 MILES NORTHWEST OF ROSEGLEN NORTH
DAKOTA TO 50 MILES EAST SOUTHEAST OF PIERRE SOUTH DAKOTA.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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.  SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.

DISCUSSION...ISOLATED STRONG/SEVERE THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG SURFACE BOUNDARY ACROSS WESTERN ND AND CENTRAL SD
DURING THE NEXT FEW HOURS.  AIRMASS IN THIS REGION IS DESTABILIZING
RAPIDLY...AND UPPER TROUGH AXIS IS APPROACHING.  LARGE HAIL APPEARS
TO BE THE PRIMARY THREAT.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM
MOTION VECTOR 24025.

...HART

480,1005 440,0980 440,1003 480,1033

Nearby

Severe Thunderstorm Watches in South Dakota, 2002 Severe Thunderstorm Watches in North Dakota, 2002 Every severe thunderstorm 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.