Alert archive / Minnesota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 335, NWS Grand Forks, ND

September 1, 2002Pennington County, Red Lake County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Sep 1, 2002, 12:24 AM CDT for Pennington County, Red Lake County, Minnesota. It was in force for 51 min. 2 reports 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
Sep 1, 2002, 12:24 AM CDT (05:24 UTC)
Expired
Sep 1, 2002, 1:15 AM CDT
In force
51 min
Issued by
NWS Grand Forks, ND
Area
Counties, with a storm outline in the text

Counties Pennington County, MN, Red Lake County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 106 km from the middle of the area, began a volume at 05:25 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

TimeReportWhereRemark
Sep 1, 12:45 AM CDTThunderstorm WindThief River Falls, MNLarge cottonwood trees were uprooted and a grain bin was demolished.
Sep 1, 12:55 AM CDTThunderstorm Wind 61 EThief River Falls, 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.

IssuedProductOfficeLasted
Aug 31, 9:55 PM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 5.4 hours before the alert went out and 215 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-pSkew-T log-p diagram, International Fa, MN at 00:00Z on 2002-09-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2440 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, International Fa, MN at 00:00Z on 2002-09-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 140 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
2440 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
988 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
140 m²/s²
0-3 km storm-relative helicity
180 m²/s²
Significant tornado parameter
1.4
Supercell composite
6.5

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 31, 8:45 PM CDT, 3 hours 39 minutes earlier.

Area forecast discussion, Aug 31, 8:45 PM CDT, 3 hours 39 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
845 PM CDT SAT AUG 31 2002

SEVERE THUNDERSTORMS ARE CONFINED SO FAR TO EXTREME NORTHERN RED
RIVER VALLEY BUT TRAINING THUNDERSTORMS ARE APPROACHING ON SEVERAL
FRONTS AT WEST/SOUTHWEST SIDE OF CWA. BELIEVE THE AVN WAS MOST
CORRECT IN PLACEMENT OF HEAVIEST RAIN TONIGHT BUT FLOOD WATCH IN
EFFECT THROUGHOUT REGION IS STILL VALID WITH SATURATED SOILS IN
ABUNDANCE. WILL LEAVE ZONES BASICALLY ALONE BUT WILL ADD EMPHASIS
ON FLOOD POTENTIAL AS NONE WAS INCLUDED EARLIER.

.FGF...FLASH FLOOD WATCH ENTIRE CWA TONIGHT.
       SEVERE THUNDERSTORM WATCH TIL MIDNIGHT NORTH HALF EXCEPT LAKE
       OF THE WOODS AND BELTRAMI COUNTIES.
GV

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 31, 8:53 PM CDTSevere Thunderstorm WarningFGFKittson52 min
Aug 31, 11:46 PM CDTSevere Thunderstorm WarningFGFClay44 min
Sep 1, 12:02 AM CDTSevere Thunderstorm WarningFGFMarshall43 min
Sep 1, 12:20 AM CDTSevere Thunderstorm WarningFGFPolk40 min
Sep 1, 12:52 AM CDTSevere Thunderstorm WarningFGFNorman, Polk38 min
Sep 1, 1:16 AM CDTSevere Thunderstorm WarningFGFRoseau29 min
Sep 1, 1:50 AM CDTSevere Thunderstorm WarningFGFBeltrami40 min
Aug 31, 7:13 PM CDTSevere Thunderstorm WarningFGFCavalier47 min
Aug 31, 7:22 PM CDTFlash Flood WarningFGFCavalier4 hr
Aug 31, 7:45 PM CDTSevere Thunderstorm WarningFGFPembina45 min
Aug 31, 7:56 PM CDTSevere Thunderstorm WarningFGFCavalier34 min
Aug 31, 8:32 PM CDTSevere Thunderstorm WarningFGFCavalier43 min
Aug 31, 8:42 PM CDTTornado WarningFGFCavalier33 min
Aug 31, 9:00 PM CDTSevere Thunderstorm WarningFGFBenson, Towner45 min
Aug 31, 9:11 PM CDTSevere Thunderstorm WarningFGFCavalier49 min
Aug 31, 9:43 PM CDTSevere Thunderstorm WarningFGFBenson, Ramsey, Towner62 min
Aug 31, 9:47 PM CDTSevere Thunderstorm WarningFGFPembina43 min
Aug 31, 10:02 PM CDTSevere Thunderstorm WarningFGFCavalier43 min
Aug 31, 10:07 PM CDTFlash Flood WarningFGFCavalier, Pembina3 hr
Aug 31, 10:20 PM CDTSevere Thunderstorm WarningFGFBarnes, Griggs55 min
Aug 31, 10:30 PM CDTSevere Thunderstorm WarningFGFPembina45 min
Aug 31, 10:45 PM CDTSevere Thunderstorm WarningFGFCavalier45 min
Aug 31, 10:52 PM CDTSevere Thunderstorm WarningFGFCass53 min
Aug 31, 11:15 PM CDTSevere Thunderstorm WarningFGFBarnes30 min
Aug 31, 11:18 PM CDTSevere Thunderstorm WarningFGFPembina42 min
Sep 1, 12:28 AM CDTSevere Thunderstorm WarningFGFSargent47 min
Sep 1, 1:19 AM CDTSevere Thunderstorm WarningFGFRichland41 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2002Every 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.