Alert archive / Minnesota / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 232, NWS Grand Forks, ND

July 31, 2001Pennington County, Polk County, Red Lake County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 31, 2001, 11:57 AM CDT for Pennington County, Polk County, Red Lake County, Minnesota. It was in force for 48 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
Jul 31, 2001, 11:57 AM CDT (16:57 UTC)
Expired
Jul 31, 2001, 12:45 PM CDT
In force
48 min
Issued by
NWS Grand Forks, ND
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Pennington County, MN, Polk County, MN, Red Lake County, MN

The radar

The Fargo/Grand Forks radar (KMVX), 95 km from the middle of the area, began a volume at 16:57 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
Jul 31, 12:15 PM CDTHail 0.75Wylie, 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, 5.0 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-pSkew-T log-p diagram, International Fa, MN at 12:00Z on 2001-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2851 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 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 12:00Z on 2001-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 22 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
2851 J/kg
Mixed-layer CIN
-13 J/kg
Mixed-layer LCL
485 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
22 m²/s²
0-3 km storm-relative helicity
179 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.8

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KFGF 311658
SVRFAR

MNC113-119-125-311745-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EASTERN ND-GRAND FORKS
1157 AM CDT TUE JUL 31 2001

THE NATIONAL WEATHER SERVICE IN GRAND FORKS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

  PENNINGTON COUNTY IN NORTHWEST MINNESOTA...
  NORTH CENTRAL POLK COUNTY IN NORTHWEST MINNESOTA AND   
  WESTERN RED LAKE COUNTY IN NORTHWEST MINNESOTA.
  INCLUDING THE CITY OF THIEF RIVER FALLS...

* UNTIL 1245 PM CDT.

* AT 1152 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER DOROTHY...OR ABOUT 19 MILES SOUTHWEST     
  OF THIEF RIVER FALLS...MOVEMENT WAS TO THE NORTHEAST AT 50 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...

  RED LAKE FALLS AT NOON CDT...
  ST. HILAIRE AT 1205 PM CDT...
  HAZEL AT 1210 PM CDT AND
  PLUMMER AT 1215 PM CDT.

REMEMBER SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES WITH LITTLE OR NO ADVANCE WARNING.

LAT...LON 4811 9655 4783 9656 4781 9588 4815 9579


$$
04

NNNN

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 Jul 31, 10:30 AM CDT, 1 hour 27 minutes earlier.

Area forecast discussion, Jul 31, 10:30 AM CDT, 1 hour 27 minutes before
FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
1030 AM CDT TUE JUL 31 2001

FORECAST CHALLENGE FOR TODAY IS PCPN. CURRENT SATELLITE IMAGERY
SHOWS CWFA BASICALLY CLOUDY WITH TSRA IN ND SIDE OF CWFA. KMVX
SHOWING TSRA COMPLEX MOVING INTO RED RIVER VALLEY. LATEST MSAS SFC
PRESSURE ANALYSIS HAS LOW PRESSURE IN CENTRAL ND...WITH FRONT
EXTENDING ALONG A JMS-GFK-HCO LINE. WHEN COMPARING INITIALIZATION
CONDITIONS TO MODELS...ETA BEST MATCH. WITH PW'S AROUND 2.O
INCH...GOOD 850 MB LLJ...THETA-E RIDGE...AND 700MB TROF
APPROACHING...TSRA WITH HEAVY RAIN STILL LOOKS GOOD AS WELL AS SOME
SVR. THEREFORE...CURRENT FORECAST PRETTY WELL IN HAND. ONLY MINOR
CHANGES NEEDED.

.FGF...FLASH FLOOD WATCH FULL CWFA TODAY.

NG

In the hours before

Local storm report, Jul 31, 6:05 AM CDT, 5 hours 52 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, 6:47 AM CDT, 5 hours 10 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, 6:59 AM CDT, 4 hours 58 minutes 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 office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 4:11 AM CDTSevere Thunderstorm WarningFGFNorman, Polk34 min
Jul 31, 4:11 AM CDTSevere Thunderstorm WarningFGFPennington, Red Lake34 min
Jul 31, 4:11 AM CDTSevere Thunderstorm WarningFGFMarshall34 min
Jul 31, 4:47 AM CDTSevere Thunderstorm WarningFGFPennington, Polk, Red Lake28 min
Jul 31, 4:47 AM CDTSevere Thunderstorm WarningFGFBeltrami, Kittson, Marshall, Roseau28 min
Jul 31, 4:47 AM CDTSevere Thunderstorm WarningFGFClearwater28 min
Jul 31, 5:37 AM CDTSevere Thunderstorm WarningFGFBeltrami, Lake of the Woods38 min
Jul 31, 11:21 AM CDTSevere Thunderstorm WarningFGFPolk39 min
Jul 31, 12:11 PM CDTSevere Thunderstorm WarningFGFMarshall64 min
Jul 31, 12:43 PM CDTSevere Thunderstorm WarningFGFPennington32 min
Jul 31, 12:46 PM CDTSevere Thunderstorm WarningFGFBeltrami, Lake of the Woods59 min
Jul 31, 1:20 PM CDTSevere Thunderstorm WarningFGFPennington, Polk25 min
Jul 31, 1:35 PM CDTSevere Thunderstorm WarningFGFMarshall40 min
Jul 31, 1:44 PM CDTSevere Thunderstorm WarningFGFLake of the Woods31 min
Jul 31, 2:15 PM CDTSevere Thunderstorm WarningFGFBeltrami, Marshall30 min
Jul 31, 4:35 PM CDTFlash Flood WarningFGFMarshall6 hr
Jul 31, 4:39 PM CDTFlash Flood WarningFGFPolk4 hr
Jul 31, 4:54 PM CDTSevere Thunderstorm WarningFGFPolk51 min
Jul 31, 5:16 PM CDTSevere Thunderstorm WarningFGFLake of the Woods, Roseau44 min
Jul 31, 5:39 PM CDTTornado WarningFGFBeltrami, Lake of the Woods36 min
Jul 31, 6:05 PM CDTFlash Flood WarningFGFBeltrami, Lake of the Woods, Marshall, Roseau6 hr
Jul 31, 6:13 PM CDTSevere Thunderstorm WarningFGFClay32 min
Jul 31, 6:15 PM CDTTornado WarningFGFLake of the Woods30 min
Jul 31, 6:23 PM CDTFlash Flood WarningFGFPennington, Polk, Red Lake6 hr
Jul 31, 6:24 PM CDTSevere Thunderstorm WarningFGFNorman36 min
Jul 31, 6:54 PM CDTSevere Thunderstorm WarningFGFPolk, Red Lake36 min
Jul 31, 6:58 PM CDTSevere Thunderstorm WarningFGFNorman32 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.