Alert archive / North Dakota / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 660

August 31, 20026 counties in Minnesota; 9 counties in North Dakota

The Storm Prediction Center issued this severe thunderstorm watch at Aug 31, 2002, 7:00 PM CDT for 6 counties in Minnesota; 9 counties in North Dakota. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued: Aug 31, 2002, 7:00 PM CDT (00:00 UTC)
Expired: Sep 1, 2002, 12:00 AM CDT
In force: 5 hr
Issued by: the Storm Prediction Center

Counties Kittson County, MN, Marshall County, MN, Pennington County, MN, Polk County, MN, Red Lake County, MN, Roseau County, MN, Benson County, ND, Cavalier County, ND, Eddy County, ND, Grand Forks County, ND, Nelson County, ND, Pembina County, ND, Ramsey County, ND, Towner County, ND, Walsh County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 84 km from the middle of the area, began a volume at 00:04 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

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

Issued	Product	Office	Counties	Lasted
Aug 31, 7:13 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier	47 min
Aug 31, 7:22 PM CDT	Flash Flood Warning	FGF	Cavalier	4 hr
Aug 31, 7:45 PM CDT	Severe Thunderstorm Warning	FGF	Pembina	45 min
Aug 31, 7:56 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier	34 min
Aug 31, 8:32 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier	43 min
Aug 31, 8:42 PM CDT	Tornado Warning	FGF	Cavalier	33 min
Aug 31, 8:53 PM CDT	Severe Thunderstorm Warning	FGF	Kittson	52 min
Aug 31, 9:00 PM CDT	Severe Thunderstorm Warning	FGF	Benson, Towner	45 min
Aug 31, 9:11 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier	49 min
Aug 31, 9:43 PM CDT	Severe Thunderstorm Warning	FGF	Benson, Ramsey, Towner	62 min
Aug 31, 9:47 PM CDT	Severe Thunderstorm Warning	FGF	Pembina	43 min
Aug 31, 10:02 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier	43 min
Aug 31, 10:07 PM CDT	Flash Flood Warning	FGF	Cavalier, Pembina	3 hr
Aug 31, 10:30 PM CDT	Severe Thunderstorm Warning	FGF	Pembina	45 min
Aug 31, 10:45 PM CDT	Severe Thunderstorm Warning	FGF	Cavalier	45 min
Aug 31, 11:18 PM CDT	Severe Thunderstorm Warning	FGF	Pembina	42 min

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 0.0 hours before the alert went out and 260 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: 1564 J/kg
Mixed-layer CIN: -12 J/kg
Mixed-layer LCL: 2744 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.1

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 010002
SEL0  
SPC WW 010000
MNZ000-NDZ000-010500-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 660
STORM PREDICTION CENTER NORMAN OK
700 PM CDT SAT AUG 31 2002

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

   NORTHWEST MINNESOTA                          
   NORTHEAST NORTH DAKOTA                       

EFFECTIVE THIS SATURDAY NIGHT FROM 700 PM UNTIL MIDNIGHT 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 100 STATUTE MILES
EAST AND WEST OF A LINE FROM 35 MILES SOUTHWEST OF GRAND FORKS
NORTH DAKOTA TO 75 MILES NORTH OF GRAND FORKS NORTH 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.

OTHER WATCH INFORMATION...  CONTINUE...WW 657...WW 658...WW 659...

DISCUSSION...STRONG/SEVERE THUNDERSTORMS CONTINUE TO MOVE EWD ALONG
NERN ND/SERN MANITOBA BORDER.  ADDITIONAL STORMS MAY DEVELOP SWWD
ALONG THE COLD FRONT MOVING ACROSS CENTRAL/ERN ND AS LOW LEVEL
CONVERGENCE INCREASES THIS EVENING.  AIR MASS IS MOIST AND QUITE
UNSTABLE WITH MLCAPE TO 2500 J/KG...AND 40-50 KT WSWLY MID LEVEL
FLOW IS CONTRIBUTING TO SUFFICIENT DEEP LAYER SHEAR FOR SEVERE
STORMS TO PERSIST INTO TONIGHT. 


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 24035.


...WEISS

490,0945 473,0953 473,0995 490,0992

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 31, 9:55 PM CDT	Severe Thunderstorm Watch	SPC	Clay, Clearwater, Kittson, Lake of the Woods, Mahnomen, Marshall and 6 more	6 hr
Sep 1, 12:45 PM CDT	Severe Thunderstorm Watch	SPC	Anoka, Benton, Carver, Chisago, Dakota, Hennepin and 17 more	6 hr
Sep 1, 3:45 PM CDT	Severe Thunderstorm Watch	SPC	Chippewa, Cottonwood, Jackson, Kandiyohi, Lac qui Parle, Lincoln and 9 more	5 hr
Sep 1, 5:20 PM CDT	Severe Thunderstorm Watch	SPC	Blue Earth, Brown, Dodge, Faribault, Fillmore, Freeborn and 11 more	6 hr
Sep 1, 6:15 PM CDT	Severe Thunderstorm Watch	SPC	Pine, Washington	6 hr

Nearby

Severe Thunderstorm Watches in North Dakota, 2002 Severe Thunderstorm Watches in Minnesota, 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; radar from the NEXRAD Level II archive.