Northern Minnesota Severe Thunderstorms, July 26, 2021

picture of damage
Wind damage to trees affecting a vehicle at the Department of Natural Resources' regional headquarters in Grand Rapids, from storms on July 26, 2021.
Courtesy: Minnesota DNR staff

Strong thunderstorms produced three confirmed tornadoes, reports of very large hail, and wind damage across portions of northern Minnesota on Monday July 26, 2021.

An isolated intense thunderstorm formed initially in northwestern Minnesota, not far from Bemidji, just after 4 PM, with the first report of damaging hail reported in Red Lake, Beltrami County, just after 5 PM. Law enforcement reported a tornado with structural damage at 5:13 PM in Red Lake, just minutes after the initial large hail report.

The storm moved southeasterly through Beltrami County, and began producing very large hail. Golfball-sized hail was reported in Blackduck, with baseball-sized hail then reported in Tenstrike and Bena (Cass County) between 6 PM and 6:35 PM. Structural damage was also reported in Tenstrike.

The Grand Forks National Weather Service office confirmed three separate tornadoes: an EF-1 with estimated peak winds of 95 mph that  moved southeastward off of Lower Red Lake and passed through the Red Lake community; another EF-1 with estimated peak winds of 95 mph, several miles to the east, just east of Redby; and an EF-0 with estimated 80 mph winds to the south, near Nebish.

Additional severe thunderstorms formed to the east of the original cell, with significant tree damage and power outages reported from the  Grand Rapids area into northern Aitkin County, tree damage reported in parts of St. Louis County, including the Duluth area, and towards Two Harbors.

The storms also produced some heavy but beneficial rains, with parts of Itasca, Carlton, and St. Louis Counties receiving over an inch of precipitation. Unfortunately, these storms were quite isolated in nature, so only a small proportion of the state received any rain at all.

For most of their lives in Minnesota, these thunderstorms were "supercells," meaning they were rotating around a vertical axis. Supercells tend to form in conditions that allow them to isolate themselves and attain greater longevity than typical storms. These same conditions often also promote severe weather, so supercells are the most potent class of thunderstorms. These particular cells formed near the edge of a very warm and humid air mass, where winds aloft were strong and also strengthened with height.

Below are summaries from the National Weather Service offices in Grand Forks and Duluth.

 

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE GRAND FORKS ND
952 PM CDT MON JUL 26 2021
..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0507 PM     HAIL             RED LAKE                47.88N 95.02W
07/26/2021  E1.25 INCH       BELTRAMI           MN   LAW ENFORCEMENT
QUARTER SIZE HAIL REPORTED IN THE AREA.
0513 PM     TORNADO          RED LAKE                47.88N 95.02W
07/26/2021                   BELTRAMI           MN   LAW ENFORCEMENT
PRELIMINARY REPORT OF OBSERVED TORNADO.
REPORTS OF SOME STRUCTURAL DAMAGE.
0535 PM     HAIL             BLACKDUCK               47.73N 94.55W
07/26/2021  M1.75 INCH       BELTRAMI           MN   PUBLIC
GOLF BALL SIZED HAIL REPORTED AT THE
BLACKDUCK GOLF COURSE.
0544 PM     HAIL             TURTLE RIVER            47.59N 94.76W
07/26/2021  NULLNAN INCH     BELTRAMI           MN   LAW ENFORCEMENT
DAMAGING HAIL.
0544 PM     TSTM WND DMG     TURTLE RIVER            47.59N 94.76W
07/26/2021                   BELTRAMI           MN   LAW ENFORCEMENT
REPORT OF TREES BENT.
0600 PM     HAIL             TENSTRIKE               47.66N 94.68W
07/26/2021  E2.75 INCH       BELTRAMI           MN   PUBLIC
REPORT OF BASEBALL SIZE HAIL AND WINDOW
DAMAGE VIA SOCIAL MEDIA.
0600 PM     HAIL             TENSTRIKE               47.66N 94.68W
07/26/2021  M1.75 INCH       BELTRAMI           MN   LAW ENFORCEMENT
GOLF BALL SIZED HAIL.
0600 PM     TSTM WND DMG     TENSTRIKE               47.66N 94.68W
07/26/2021                   BELTRAMI           MN   LAW ENFORCEMENT
STRUCTURAL DAMAGE REPORTED.
0613 PM     HAIL             PENNINGTON              47.48N 94.48W
07/26/2021  M2.50 INCH       BELTRAMI           MN   PUBLIC
2.5 INCH HAIL REPORTED VIA SOCIAL MEDIA WITH
IMAGE.
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE DULUTH MN
1005 AM CDT TUE JUL 27 2021
..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0615 PM     HAIL             5 NE SCHLEY             47.41N 94.34W
07/26/2021  E1.50 INCH       CASS               MN   PUBLIC
ESTIMATE AT LEAST PING-PONG BALL SIZE HAIL
PER VIDEOS POSTED ON SNAPCHAT. TIME AND
LOCATION ESTIMATED.
0634 PM     HAIL             BENA                    47.34N 94.21W
07/26/2021  M3.00 INCH       CASS               MN   PUBLIC
HAIL UP TO 2.9 INCHES MEASURED NEAR BENA.
PHOTO AND REPORT VIA TWITTER. TIME ESTIMATED
FROM RADAR.
0647 PM     HAIL             5 NE DEER RIVER         47.40N 93.72W
07/26/2021  M0.70 INCH       ITASCA             MN   TRAINED SPOTTER
DIME SIZE HAIL AND GUSTY WINDS.
0650 PM     TSTM WND DMG     3 NW SKIBO              47.52N 92.05W
07/26/2021                   ST. LOUIS          MN   911 CALL CENTER
TREE DOWN IN BASSETT TOWNSHIP.
0655 PM     TSTM WND DMG     COHASSET                47.26N 93.63W
07/26/2021                   ITASCA             MN   PUBLIC
LARGE PINE TREE UPROOTED. REPORT VIA SOCIAL
MEDIA. TIME ESTIMATED FROM RADAR.
0700 PM     TSTM WND DMG     1 WNW ZIM               47.31N 92.63W
07/26/2021                   ST. LOUIS          MN   TRAINED SPOTTER
16 INCH TREE UPROOTED.
0706 PM     HAIL             3 NE LA PRAIRIE         47.26N 93.45W
07/26/2021  U1.00 INCH       ITASCA             MN   PUBLIC
REPORT FROM MPING: QUARTER (1.00 IN.).
0708 PM     TSTM WND DMG     GRAND RAPIDS            47.23N 93.52W
07/26/2021                   ITASCA             MN   TRAINED SPOTTER
BIG BRANCHES OFF TREES AND A FLAG POLE
SNAPPED IN HALF DUE TO DAMAGING WINDS.
LOCATION APPROXIMATE.
0712 PM     TSTM WND GST     1 SSE GRAND RAPIDS      47.22N 93.52W
07/26/2021  M54 MPH          ITASCA             MN   AWOS
AWOS STATION KGPZ GRAND RAPIDS AIRPORT.
0713 PM     HAIL             3 S BOVEY               47.24N 93.40W
07/26/2021  M1.00 INCH       ITASCA             MN   COCORAHS
MN-IT-39.
0714 PM     HAIL             2 SSW COLERAINE         47.28N 93.44W
07/26/2021  U1.00 INCH       ITASCA             MN   PUBLIC
REPORT FROM MPING: QUARTER (1.00 IN.).
0716 PM     HAIL             1 WSW BLACKBERRY        47.17N 93.42W
07/26/2021  U1.00 INCH       ITASCA             MN   PUBLIC
REPORT FROM MPING: QUARTER (1.00 IN.).
0720 PM     HAIL             2 WSW BOVEY             47.28N 93.43W
07/26/2021  E0.88 INCH       ITASCA             MN   PUBLIC
A FEW BRANCHES DOWN AS WELL.
0720 PM     HAIL             BLACKBERRY              47.18N 93.39W
07/26/2021  M1.00 INCH       ITASCA             MN   TRAINED SPOTTER
HAIL STILL FALLING AT TIME OF REPORT.
LOCATION APPROXIMATE.
0728 PM     TSTM WND DMG     GRAND RAPIDS            47.23N 93.52W
07/26/2021                   ITASCA             MN   TRAINED SPOTTER
LOCATION APPROXIMATE. MARBLE SIZE HAIL,
APPROXIMATELY 9 80 FOOT TALL NORWAY PINE
TREES UPROOTED.
0736 PM     TSTM WND DMG     1 SSE TWO HARBORS       47.02N 91.67W
07/26/2021                   LAKE               MN   TRAINED SPOTTER
TOP PART OF A HEALTHY PINE TREE KNOCKED
OVER, PUNCTURING GARAGE ROOF.
0740 PM     TSTM WND DMG     JACOBSON                47.00N 93.26W
07/26/2021                   AITKIN             MN   911 CALL CENTER
TREES DOWN IN JACOBSON. FIRE DEPT ALSO
DISPATCHED TO POWERLINE DOWN. TIME RADAR
ESTIMATED.
0751 PM     HAIL             2 ENE CULVER            46.94N 92.52W
07/26/2021  M0.75 INCH       ST. LOUIS          MN   TRAINED SPOTTER
PENNY SIZE HAIL AND GUSTY WINDS BUT NO
DAMAGE ASIDE FROM SOME LEAVES BLOWN OFF
TREES.
0801 PM     HAIL             4 NNW HERMANTOWN        46.85N 92.28W
07/26/2021  U0.75 INCH       ST. LOUIS          MN   PUBLIC
REPORT FROM MPING: DIME (0.75 IN.).
0802 PM     HAIL             1 WSW SAGINAW           46.85N 92.46W
07/26/2021  M0.88 INCH       ST. LOUIS          MN   TRAINED SPOTTER
HAIL AND GUSTY WINDS.
0806 PM     HAIL             NWS DULUTH              46.84N 92.21W
07/26/2021  M0.50 INCH       ST. LOUIS          MN   OFFICIAL NWS OBS
0810 PM     HAIL             2 NNE DULUTH            46.81N 92.11W
07/26/2021  E1.00 INCH       ST. LOUIS          MN   AMATEUR RADIO
MAINLY PEA TO DIME SIZE HAIL. A FEW QUARTER
SIZE HAILSTONES. TIME ESTIMATED BY SPOTTER.
0811 PM     HAIL             4 NE HERMANTOWN         46.84N 92.18W
07/26/2021  U1.00 INCH       ST. LOUIS          MN   PUBLIC
REPORT FROM MPING: QUARTER (1.00 IN.).
0811 PM     TSTM WND GST     2 NNW SUPERIOR          46.75N 92.10W
07/26/2021  M62 MPH          LSZ145             WI   MESONET
MESONET STATION MN081 BLATNIK BRIDGE.
0815 PM     TSTM WND DMG     3 NE DULUTH             46.81N 92.08W
07/26/2021                   ST. LOUIS          MN   NWS EMPLOYEE
HALF OF A TREE FALLEN OVER A HOUSE. NICKEL
SIZE HAIL. TIME APPROXIMATE.
0818 PM     MARINE TSTM WIND 1 ESE DULUTH            46.78N 92.09W
07/26/2021  M51 MPH          ST. LOUIS          MN   MESONET
STATION DULM5 DULUTH HARBOR.
0912 PM     HAIL             4 SE SILICA             47.23N 92.95W
07/26/2021  M1.00 INCH       ST. LOUIS          MN   TRAINED SPOTTER
12 MILES SOUTH OF HIBBING.

 

Last modified July 27. 2021