Alert archive / Minnesota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 306, NWS Grand Forks, ND

August 28, 2002Otter Tail County, Wadena County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 28, 2002, 8:46 PM CDT for Otter Tail County, Wadena County, Minnesota. It was in force for 44 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Aug 28, 2002, 8:46 PM CDT (01:46 UTC)
Expired: Aug 28, 2002, 9:30 PM CDT
In force: 44 min
Issued by: NWS Grand Forks, ND
Area: Counties, with a storm outline in the text

Counties Otter Tail County, MN, Wadena County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 189 km from the middle of the area, began a volume at 01:46 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.

What was reported inside it

Time	Report	Where	Remark
Aug 28, 9:25 PM CDT	Hail 0.75	Nimrod, MN

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 28, 5:35 PM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.8 hours before the alert went out and 228 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: 1255 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 1187 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Grand Forks, ND wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 28, 7:50 PM CDT, 56 minutes earlier.

Area forecast discussion, Aug 28, 7:50 PM CDT, 56 minutes before

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
750 PM CDT WED AUG 28 2002

.CURRENT OBSERVATIONAL OVERVIEW...
00Z MSAS ANALYSIS DEPICTED WEAK LOW PRESSURE OVER EXTREME NORTH
CENTRAL SOUTH DAKOTA WITH ASSOCIATED INVERTED TROUGH AXIS FROM
SOUTHEAST NORTH DAKOTA INTO WESTERN MINNESOTA. LATEST SATELLITE AND
KMVX RADAR INDICATED STRONG/SEVERE THUNDERSTORMS FIRING ALONG AND
AHEAD OF TROUGH AXIS IN VICINITY OF STRONG INSTABILITY AND ENHANCED
MOISTURE FLUX CONVERGENCE.

.FORECAST DETAILS...
EXPECT STORMS TO SLOWLY WEAKEN IN TERM OF SEVERITY DURING NEXT
COUPLE OF HOURS AS DAYTIME HEATING CEASES. HOWEVER...EXPECT
FLOODING POTENTIAL TO PERSIST AS MULTICELLUAR STORMS MERGE MORE INTO
MCS SITUATION REMAINDER OF NIGHT. WILL MONITOR RADAR TRENDS DURING
NEXT FEW HOURS TO DETERMINE WHERE BEST LINGERING HEAVY THREAT EXISTS
OVERNIGHT...AND THUS PERHAPS BE ABLE HOPE TO FINE TUNE INHERITED
FLOOD WATCH.

.FGF...FLOOD WATCH ALL OF FA EXCEPT DVL REGION AND EXTREME NE ND AND
NW MN.

BERG

In the hours before

Local storm report, Aug 28, 6:16 PM CDT, 2 hours 30 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
616 PM CDT WED AUG 28 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0545 PM    4 SE HITTERDAL            MN   .75 INCH HAIL
08/28/02   CLAY                           REPORTED BY PUBLIC.

DPORTER

Local storm report, Aug 28, 6:33 PM CDT, 2 hours 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
633 PM CDT WED AUG 28 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0530 PM    9 NW PELICAN RAPIDS       MN   1.00 INCH HAIL
08/28/02   OTTER TAIL                     REPORTED BY PUBLIC.

0600 PM    3 E WAUBUN                MN   .88 INCH HAIL
08/28/02   MAHNOMEN                       REPORTED BY CO-OP OBSERVER.

DPORTER

Local storm report, Aug 28, 6:42 PM CDT, 2 hours 4 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
642 PM CDT WED AUG 28 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0635 PM    SABIN                     MN   .75 INCH HAIL
08/28/02   CLAY                           REPORTED BY CO-OP
                                          OBSERVER.

DPORTER

Local storm report, Aug 28, 6:59 PM CDT, 1 hour 47 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
659 PM CDT WED AUG 28 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0530 PM    2 N OGEMA                 MN   1.75 INCH HAIL
08/28/02   BECKER                         REPORTED BY PUBLIC.

0635 PM    SABIN                     MN   .75 INCH HAIL
08/28/02   CLAY

DPORTER

Local storm report, Aug 28, 7:17 PM CDT, 1 hour 29 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
717 PM CDT WED AUG 28 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0705 PM    2 NE AYR                  ND   1.00 INCH HAIL
08/28/02   CASS                           REPORTED BY PUBLIC.

0715 PM    AYR                       ND   1.00 INCH HAIL
08/28/02   CASS

DPORTER

Local storm report, Aug 28, 7:40 PM CDT, 1 hour 6 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND FORKS, ND
740 PM CDT WED AUG 28 2002

TIME(CDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0725 PM    7 NW VERGAS               MN   .75 INCH HAIL
08/28/02   OTTER TAIL                     REPORTED BY PUBLIC.

DPORTER

The office that day

Everything else NWS Grand Forks, ND issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 28, 7:09 PM CDT	Severe Thunderstorm Warning	FGF	Becker, Otter Tail	51 min
Aug 28, 7:58 PM CDT	Severe Thunderstorm Warning	FGF	Becker, Hubbard	47 min
Aug 28, 8:05 PM CDT	Severe Thunderstorm Warning	FGF	Otter Tail	40 min
Aug 28, 10:19 PM CDT	Severe Thunderstorm Warning	FGF	Grant	41 min
Aug 28, 7:42 PM CDT	Tornado Warning	FGF	Cass	48 min
Aug 28, 8:05 PM CDT	Flash Flood Warning	FGF	Cass	6 hr

Nearby

Severe Thunderstorm Warnings in Minnesota, 2002 Every severe thunderstorm warning 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.