Flash Flood and Hail in North Dakota, July 31, 2001

Name: Flash Flood and Hail in North Dakota, July 31, 2001
Start: 2001-07-31T09:00
End: 2001-07-31T10:30
Location: North Dakota

July 31, 2001 · NWS FGF · 7 events in 4 counties and zones

5 thunderstorm wind, 1 flash flood, 1 hail, as filed by the National Weather Service.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $8,000
Crop damage: None recorded
Events: 7

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What forecasters said that day

The local office's own words before the first event, 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 the first event at Jul 31, 1:40 AM CST, 7 hours 20 minutes earlier.

Area forecast discussion, Jul 31, 1:40 AM CST, 7 hours 20 minutes before

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
240 AM CDT TUE JUL 31 2001

FCST CONCERNS TODAY...SVR POTENTIAL AND HVY RAIN THREAT.

.SHORT TERM...
CURRENT FRONT LOCATED ACROSS NW MN TO SE ND THEN TO WRN SD...NR A
KROX-KGFK-KJMS-KMBG LINE.  VERY HIGH DEW PTS ALONG AND AHD OF FRONT
WITH 80 DEW PTS POOLING FROM FARGO TO WADENA/STAPLES.  MCS MOVING
INTO ERN ND EARLY THIS AM SHOULD CONTINUE TO TRACK NORTHEAST.  RUC
ANALYSIS AND VAD WIND PROFILES SHOW LOW LEVEL JET OF 40KTS OVER ERN
SD INTO SE ND AND MN...WITH FAVORABLE LEFT QUAD OVER ERN ND WHICH
SHOULD AID IN KEEPING ELEVATED CONVECTION GOING EARLY THIS MORNING.
OBVIOUSLY...ATMOS VERY JUICED UP WITH HVY RAIN A GOOD BET WITH ANY
STORMS THAT FORM TODAY AND THIS EVENING.  PWATS FROM ETA/MESOETA 2
TO 2.5 INCHES.  THUS WILL MAINTAIN FFA FOR ERN ND TODAY...BUT WILL
ALTER TIMING FOR NW MN TO THIS AFTN/EVE AS BEST CONVECTION NOT
EXPECTED IN ERN CWFA TIL LATE TODAY AND EARLY TONIGHT.  COORD WITH
MPX/DLH.

SFC MAP SHOWS WK SFC LOWS OVER SE WYOMING AND OVER NCNTRL SD.  BUT
MODELS DO AGREE THAT STRONG SHORT WAVE MOVING THRU MT/ALBERTA WILL
MOVE ENE AND HELP DEEPEN THE SFC LOW AS IT MOVES NORTHEAST INTO ERN
ND THIS AFTN.  FOCUS OF HVY RAIN SHOULD BE ALONG AND JUST NORTH OF
FRONT THIS MORNING...BUT THEN FOCUS WILL SHIFT INTO MN THIS
AFTN/EVENING AS LOW MOVES NORTHEAST AND DRAGS FRONT INTO VERY JUICED
ENVIRONMENT.  SVR THREAT MOSTLY THIS MORNING FOR ND...THEN VALLEY
EAST INTO MN LATER THIS AFTN/EVENING AS COLD FRONT MOVES THROUGH.
STRONG DRY PUNCH AT 70H MOVES INTO MN BY 06Z WHICH MAY ENHANCE
SQUALL LINE POTENTIAL.

AS FOR TEMPS/WIND...GUSTY SOUTH WINDS AHD OF DEEPENING LOW IN WCNTRL
MN A GOOD BET SO WILL GO 20-30 MPH AND GUSTY IN ZFP THIS AFTN.
TEMPS WILL APPROACH 90 IN THAT AREA AS WELL...AND WITH HIGH DEW PTS
THIS WILL APPROACH HEAT ADVISORY CONDITIONS.  ATTM WILL NOT HEADLINE
FOR HEAT OR WIND ADVISORIES IN WCNTRL MN AS WANT TO FOCUS ON HVY
RAIN THREAT THIS AFTN/EVE.

.LONGER TERM...
SYSTEM TO MOVE EAST TONIGHT WITH CONVECTION EXITING MN CWFA AFTER
06Z.  THEN RELIEF WILL COME IN LATE TONIGHT AND WEDNESDAY AS LOWER
DEW PTS OVERSPREAD THE AREA.  WITH SRN END OF 50H TROUGH SWINGING
ALONG INTERNATIONAL BORDER COULD BE SOME INSTABILITY SHOWERS FAR NE
ND AND NW MN.  ATTM WILL KEEP IT DRY AND LET LATER SHIFTS EVAULATE
THIS.

.EXTENDED...
NO CHANGES TO EXTENDED.  50H RIDGE RE-BUILDS IN MN THIS WEEEKEND
SETTING THE STAGE FOR A RETURN TO WARMER AND HUMID WEATHER THIS
WEEKEND.  POTENTIAL FOR SOME TSRA AS WELL ESPLY SUNDAY AS FRONT
TRIES TO ADVANCE EAST.

.FGF...FLASH FLOOD WATCH EASTERN NORTH DAKOTA AND THE RED RIVER
VALLEY TODAY AND NORTHWEST AND WEST CENTRAL MINNESOTA THIS AFTERNOON
AND EVENING.

RIDDLE

In the hours before

Local storm report, Jul 31, 5:05 AM CST, 3 hours 55 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE EASTERN NORTH DAKOTA/GRAND FORKS
605 AM CDT TUE JUL 31 2001

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

0240 AM    VALLEY CITY               ND   WIND DAMAGE
07/31/01   BARNES                         TREES DOWN

0357 AM    HALSTAD                   MN   67 MPH TSTM GUST
07/31/01   NORMAN

0417 AM    HAWLEY                    MN   .88 INCH HAIL
07/31/01   CLAY

0425 AM    CROOKSTON                 MN   WIND DAMAGE
07/31/01   POLK                           4-5 INCH DIAMETER LIMBS
                                          DOWN

0425 AM    GENTILLY                  MN   WIND DAMAGE
07/31/01   POLK                           4-5 INCH DIAMETER LIMBS
                                          DOWN

Special weather statement, Jul 31, 5:47 AM CST, 3 hours 13 minutes before

MNZ001>009-013>017-022>024-027-028-311250-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
647 AM CDT TUE JUL 31 2001

...SEVERE THUNDERSTORM WATCH NUMBER 645 FOR NORTHWEST MINNESOTA HAS
BEEN CANCELLED....

THE SEVERE THUNDERSTORMS HAVE MOVED OUT OF NORTHWEST MINNESOTA AND
HAVE WEAKENED.  THUS THE SEVERE THUNDERSTORM WATCH THAT WAS IN
EFFECT UNTIL 8 AM CDT FOR BELTRAMI...LAKE OF THE WOODS...ROSEAU...
KITTSON...MARSHALL...PENNINGTON...RED LAKE...POLK...HUBBARD...
CLEARWATER...NORMAN...MAHNOMEN...BECKER AND CLAY COUNTIES HAS BEEN
CANCELLED.

RIDDLE

Special weather statement, Jul 31, 5:59 AM CST, 3 hours 1 minute before

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-311455-

SPECIAL WEATHER STATEMENT
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
659 AM CDT TUE JUL 31 2001

...SCATTERED SEVERE THUNDERSTORMS EXPECTED LATE THIS AFTERNOON AND
EVENING FROM THE RED RIVER VALLEY EAST INTO MINNESOTA...

SYNOPSIS...LOW PRESSURE WILL MOVE NORTHEAST INTO EASTERN NORTH
DAKOTA AND STRENGTHEN THIS AFTERNOON.  THE LOW WILL THEN MOVE
INTO MANITOBA THIS EVENING WITH A COLD FRONT MOVING EAST INTO
MINNESOTA. THE ATMOSPHERE OVER EASTERN NORTH DAKOTA AND NORTHWEST
MINNESOTA IS VERY UNSTABLE AND VERY MOIST.  AS THE LOW AND FRONT
INTERACT WITH THIS AIRMASS LATER TODAY AND EARLY EVENING
THUNDERSTORMS ARE EXPECTED TO RE-DEVELOP WITH SOME SEVERE
THUNDERSTORMS LIKELY.

AREA OF CONCERN...THERE IS A SLIGHT RISK OF SEVERE WEATHER EAST OF
A PEMBINA TO LAKOTA TO VALLEY CITY NORTH DAKOTA LINE...THEN
EAST TO INCLUDE ALL THE RED RIVER VALLEY AND NORTHWEST AND WEST
CENTRAL MINNESOTA.

TIME...BETWEEN 3 PM AND MIDNIGHT CDT.

TYPE OF HAZARD...HEAVY RAIN...STRONG WINDS...AND LARGE HAIL.

RIDDLE

The radar

The Fargo/Grand Forks radar (KMVX), 60 km away, was scanning. The volume nearest the first event began at 15:01 UTC.

Open the radar archive at this moment

Event by event

5 thunderstorm wind, 1 flash flood, 1 hail. Local standard time, as filed.

Thunderstorm Wind, Griggs

When: July 31, 9:00 AM CST
Where: Griggs County, Cooperstown
Property damage: $500
Reported by: GENERAL PUBLIC
Coordinates: 47.450, -98.117

Branches were blown down.

Thunderstorm Wind, Grand Forks

When: July 31, 9:50 AM CST
Where: Grand Forks County, 3 mi SW of Holmes
Property damage: $500
Reported by: GENERAL PUBLIC
Coordinates: 47.683, -97.350

Branches were blown down.

Flash Flood, Griggs

When: July 31, 9:55 AM CST
Where: Griggs County, Cooperstown
Property damage: $5,000
Reported by: GENERAL PUBLIC
Coordinates: 47.457, -98.237 (the zone’s center; the record gives no point)

The city park was flooded and water was 2 feet deep on streets downtown.

Thunderstorm Wind, Steele

When: July 31, 10:00 AM CST
Where: Steele County, 15 mi NE of Finley
Property damage: $500
Reported by: GENERAL PUBLIC
Coordinates: 47.667, -97.617

Branches were blown down.

Thunderstorm Wind, Traill

When: July 31, 10:08 AM CST
Where: Traill County, Hatton
Property damage: $500
Reported by: GENERAL PUBLIC
Coordinates: 47.650, -97.467

Branches were blown down.

Thunderstorm Wind, Grand Forks

When: July 31, 10:30 AM CST
Where: Grand Forks County, Grand Forks
Property damage: $1,000
Reported by: GENERAL PUBLIC
Coordinates: 47.917, -97.050

Trees were blown down.

Hail, Grand Forks

When: July 31, 10:30 AM CST
Where: Grand Forks County, 7 mi SW of Grand Forks
Measured: 0.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 47.850, -97.150

What these are

Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in North Dakota in 2001 Every state in 2001 This day in weather history Warnings in North Dakota, July 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5260449, 5260541, 5260450, 5260537, 5260538, 5260539, 5260540.