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. Golf ball-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