Alert archive / Minnesota / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 380, NWS Grand Forks, ND

September 6, 2001Marshall County, Pennington County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Sep 6, 2001, 3:25 PM CDT for Marshall County, Pennington County, Minnesota. It was in force for 35 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 6, 2001, 3:25 PM CDT (20:25 UTC)
Expired
Sep 6, 2001, 4:00 PM CDT
In force
35 min
Issued by
NWS Grand Forks, ND
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Marshall County, MN, Pennington County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 113 km from the middle of the area, began a volume at 20:28 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 6, 3:30 PM CDTHail 0.75Thief River Falls, MN
Sep 6, 3:35 PM CDTHail 1Viking, 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.

The nearest sounding before it

International Fa, MN (KINL), launched 12:00Z, 8.4 hours before the alert went out and 218 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 12:00Z on 2001-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 668 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, International Fa, MN at 12:00Z on 2001-09-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 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
668 J/kg
Mixed-layer CIN
-275 J/kg
Mixed-layer LCL
923 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
91 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Sep 6, 10:30 AM CDT, 4 hours 55 minutes earlier.

Area forecast discussion, Sep 6, 10:30 AM CDT, 4 hours 55 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
1030 AM CDT THU SEP 6 2001

VAD WND HAS BACKING FLOW ACRS WRN ND. BACKING FLOW WAS BLO 6 THSD
FEET AT BIS AND BLO 10 THSD FEET AT KMBX. VEERING WND INDICATED AT
KMVX AND ABR. ETA MODEL SOUNDING SHOWS LWR ATMOSPHERE COOLS BLO 500
HPA TDY. CAPES FCST TO BE ARND 1000-1500 J/KG TDY. CINS INCR A BIT
DURING THE DAY TO ARND 50 J/KG BY LATE AFTN. CONVECTIVE TEMPS START
HI THIS MORN AND FALL TO ARND 80 DEGREES BY LATE AFTN. 850 HPA TROF
OVR ND WL MOV INTO ERN ND THIS AFTN. MESOSCALE ANLYS SHOWS A PRES
RISE CNTR OVR SW MAN MOVG NE. SFC WNDS HAVE BECM NW AT DVL. WL KEEP
CHC OF TSRA IN FCST. WL CHECK ZONES.

.FGF...NONE.
HOPPES

In the hours before

Special weather statement, Sep 6, 1:15 PM CDT, 2 hours 10 minutes before
MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-062000-

SPECIAL WEATHER STATEMENT
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
115 PM CDT THU SEP 6 2001

...THERE IS A RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTHEAST NORTH DAKOTA AND WESTERN MINNESOTA LATE THIS AFTERNOON AND
EVENING...

SYNOPSIS...A SLOW MOVING COLD FRONT WILL ENCOUNTER A MOIST AND
MODERATELY UNSTABLE AIRMASS AS IS ADVANCES INTO EASTERN NORTH THIS
AFTERNOON...AND INTO WESTERN MINNESOTA EARLY THIS EVENING.
TEMPERATURES WILL WARM INTO THE 80S THROUGH THE AFTERNOON...AND WHEN
COMBINED WITH DEWPOINTS IN THE MIDDLE TO UPPER 60S...INSTABILITY
WILL BE MAXIMIZED ACROSS THE SOUTHERN HALF OF THE RED RIVER VALLEY.

AREA OF CONCERN...A SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS EAST
OF A HALLOCK TO COOPERSTOWN AND ELLENDALE LINE.

TIME...START AFTER 300 PM AND DIMINISH AFTER 900 PM.

TYPE OF HAZARD...MAINLY LARGE HAIL. DAMAGING WINDS WILL BE A
THREAT...AS WILL LOCALLY FLOODING RAINS FROM SLOW MOVING OR REPEAT
THUNDERSTORM EVENTS.

GUST

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 6, 4:18 PM CDTSevere Thunderstorm WarningFGFPolk, Red Lake42 min
Sep 6, 5:01 PM CDTSevere Thunderstorm WarningFGFPolk, Red Lake59 min
Sep 6, 4:30 PM CDTSevere Thunderstorm WarningFGFTraill30 min
Sep 6, 5:15 PM CDTFlash Flood WarningFGFBarnes6 hr
Sep 6, 5:18 PM CDTSevere Thunderstorm WarningFGFBarnes42 min
Sep 6, 5:45 PM CDTSevere Thunderstorm WarningFGFTraill45 min
Sep 6, 6:17 PM CDTSevere Thunderstorm WarningFGFCass28 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2001Every severe thunderstorm warning in 2001

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.