Alert archive / Minnesota / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 199, NWS Grand Forks, ND
NWS Grand Forks, ND issued this severe thunderstorm warning at Sep 11, 2026, 7:02 PM CDT for Otter Tail County, Wadena County, Minnesota. It was in force for 58 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Sep 11, 2026, 7:02 PM CDT (00:02 UTC)
- Expired
- Sep 11, 2026, 8:00 PM CDT
- In force
- 58 min
- Issued by
- NWS Grand Forks, ND
- Area
- Storm-based polygon
- Tornado
- Possible
- Damage threat
- Considerable
- Hail
- 1.75 in
- Wind
- 60.0 mph
Counties Otter Tail County, MN, Wadena County, MN
The radar
The Fargo/Grand Forks radar (KMVX), 189 km from the middle of the area, began a volume at 00:05 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.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Sep 11, 6:39 PM CDT | Severe Thunderstorm Watch | SPC | 3 hr |
The nearest sounding before it
Minneapolis, MN (KMPX), launched 00:00Z, 0.0 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.
- Mixed-layer CAPE
- 235 J/kg
- Mixed-layer CIN
- -300 J/kg
- Mixed-layer LCL
- 1734 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 143 m²/s²
- 0-3 km storm-relative helicity
- 392 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 11, 5:50 PM CDT, 1 hour 12 minutes earlier. Its key messages:
- There is a level 2 out of 5 risk for severe storms late Friday afternoon into the evening for portions of west central into north central Minnesota. Storms will be capable of producing all hazards.
- There is a high chance for soaking rainfall Sunday night into Monday night across the region which could impact outdoor activities.
Area forecast discussion, Sep 11, 5:50 PM CDT, 1 hour 12 minutes before
Area Forecast Discussion National Weather Service Grand Forks ND 550 PM CDT Fri Sep 11 2026 .KEY MESSAGES... - There is a level 2 out of 5 risk for severe storms late Friday afternoon into the evening for portions of west central into north central Minnesota. Storms will be capable of producing all hazards. - There is a high chance for soaking rainfall Sunday night into Monday night across the region which could impact outdoor activities. && .DISCUSSION... Issued at 230 PM CDT Fri Sep 11 2026 ...Synopsis... A cold front is pushing through the Northern Plains this afternoon, keeping temperatures in the north in the 60s. Meanwhile ahead of the front in far southeastern ND into west central MN, temperatures have reached the mid 80s, and dew points have climbed into the mid 60s, creating a narrow, couple of county wide axis of instability. As the cold front propagates through during the late afternoon and evening hours, thunderstorms are anticipated to develop, some of which will become strong to severe. Over the weekend, a large upper low will dig into the Pacific Northwest. Tracking eastward by late Sunday into Monday, widespread rain is forecasted for the Northern Plains. Behind this system, zonal flow will keep temperatures in the 60s most days. Rising heights late next week may bring a few 70s back into the forecast. ...Severe Risk Today... A cold front pushing eastward will provide the catalyst for thunderstorm development late this afternoon into the evening hours. Latest satellite imagery shows a developing stratocumulus field ahead of the front in Grant, Otter Tail and Wadena Counties. Capping is forecast to erode between 4 and 5 o'clock. As it erodes, the expectation is for storms to develop along the front, which should then be situated in the western reaches of the current SPC severe weather level 2 out of 5 risk area. Storms will have a narrow but rich axis of instability to work with, with MLCAPE approaching 3000 J/Kg, and effective shear of around 40 knots. Meanwhile, across eastern South Dakota, a surface low is propagating eastward/northeastward. In west central MN, closer to where this surface low will be located by this evening, more low level curvature within hodographs will foster the potential for a tornado or two. Further north (especially north of US Highway 2), hodographs are straighter, keeping the severe risk tied more to a hail and wind threat instead of tornado. One big question is how quickly storm mode becomes messy. The front should provide strong enough forcing for several updrafts to go up at once. If this occurs, the window for truly discrete storms will be shorter, leaving the potential for significant hail and a tornado or two shorter in duration. Activity will cluster and grow upscale as it pushes eastward, leaving our FA around 10 PM this evening. ...Late Weekend into Early Next Week Rainfall... A large upper low over the Pacific Northwest will propagate eastward towards the Northern Plains late Sunday into Monday. Very little instability appears in place, therefore severe weather is not expected. However, as the low tracks from southwest to northeast across the Northern Plains and Canadian Prairies, rainfall will overspread the region from west to east Sunday night, lasting into Monday. While there remains uncertainty in where the deformation band and heaviest rainfall will set up, with NBM probabilities for a half inch of rain is about 60 percent across the entire FA. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 550 PM CDT Fri Sep 11 2026 A cold will continue moving across northwest and west central MN this evening, with medium to high probabilities of thunderstorms in its vicinity, including at KBJI. A period of low VFR ceilings is also expected behind the front, but with only a 20% chance of MVFR ceilings at KTVF and KBJI this evening. North-northwest winds behind the front will decrease after sunset, but then will increase once again during the day Saturday. High confidence exists in peak gusts from 25 to 28 kts during the day Saturday at KGFK, KFAR, KDVL, and KTVF, though gusts will start to diminish toward the end of the TAF valid time (e.g., closer to 00Z). && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && DISCUSSION...Rafferty AVIATION...CJS
Hazardous weather outlook, Sep 11, 2:21 PM CDT, 4 hours 41 minutes before
Hazardous Weather Outlook National Weather Service Grand Forks ND 221 PM CDT Fri Sep 11 2026 MNZ001-002-004-005-007-008-013>015-NDZ006>008-014>016-024-026>030- 038-039-049-052-054-121930- West Polk-Norman-Kittson-Roseau-West Marshall-East Marshall- Pennington-Red Lake-East Polk-Towner-Cavalier-Pembina-Benson- Ramsey-Eastern Walsh-Eddy-Nelson-Grand Forks-Griggs-Steele-Traill- Barnes-Cass-Ransom-Sargent-Western Walsh- 221 PM CDT Fri Sep 11 2026 This hazardous weather outlook is for portions of eastern North Dakota and northwest Minnesota. .DAY ONE...This Afternoon and Tonight The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Saturday through Thursday The probability for widespread hazardous weather is low. .SPOTTER INFORMATION STATEMENT... Spotter activation may be required today. MNZ003-006-009-016-017-022>024-027>032-040-NDZ053-121930- Clay-Lake Of The Woods-North Beltrami-North Clearwater- South Beltrami-Mahnomen-South Clearwater-Hubbard-West Becker- East Becker-Wilkin-West Otter Tail-East Otter Tail-Wadena-Grant- Richland- 221 PM CDT Fri Sep 11 2026 This hazardous weather outlook is for portions of eastern North Dakota, west central and northwest Minnesota. .DAY ONE...This Afternoon and Tonight The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Saturday through Thursday There is a level 2 out of 5 risk for severe thunderstorms mid afternoon into the evening. The main hazards will be hail up the size of golf balls, damaging winds up to 70 mph, with a tornado or two possible. .SPOTTER INFORMATION STATEMENT... Spotter activation may be required today.
In the hours before
Local storm report, Sep 11, 6:39 PM CDT, 23 minutes before
Preliminary Local Storm Report
National Weather Service Grand Forks ND
639 PM CDT Fri Sep 11 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0638 PM Hail 4.8 SW Herman 45.76N 96.21W
09/11/2026 M1.25 Inch Grant MN Trained Spotter
&&Local storm report, Sep 11, 6:51 PM CDT, 11 minutes before
Preliminary Local Storm Report
National Weather Service Grand Forks ND
651 PM CDT Fri Sep 11 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0647 PM Hail 2 SSE Norcross 45.84N 96.17W
09/11/2026 M1.25 Inch Grant MN Trained Spotter
&&
TTThe office that day
Everything else NWS Grand Forks, ND issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 11, 7:05 PM CDT | Severe Thunderstorm Warning | FGF | Otter Tail | 55 min |
| Sep 11, 7:12 PM CDT | Tornado Warning | FGF | Otter Tail, Wadena | 48 min |
| Sep 11, 7:37 PM CDT | Severe Thunderstorm Warning | FGF | Wadena | 53 min |
Nearby
Severe Thunderstorm Warnings in Minnesota, 2026Every severe thunderstorm warning in 2026
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.