Tornadoes · United States · Minnesota · 2025

Unrated tornado, Norcross, Minnesota, August 21, 2025

This Unrated tornado ran 0.3 miles across Grant County on August 21, 2025, touching down at 6:18 PM CDT and reaching 30 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. EF065 to 85 mph

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. EF186 to 110 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. EF2111 to 135 mph

    Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

  4. EF3136 to 165 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. EF4166 to 200 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. EF5over 200 mph

    Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

  7. Unratedthis tornado

    The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

The record

Rating
Unrated
Date
August 21, 2025
Touchdown
6:18 PM CDT (23:18 UTC)
Lifted
6:23 PM CDT (23:23 UTC)
On the ground
5 minutes
Path length
0.3 miles (0.4 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Grant County
Touchdown point
45.870, -96.240
Lift-off point
45.870, -96.240
Record number
2508211718-02

What the Weather Service recorded

A severe thunderstorm produced quarter size hail in Pennington County in northwest MN during the evening. A cluster of storms moving into west central Minnesota also produced several brief weak landspout type tornadoes in Grant County, but produced no reported damage.

Relayed from emergency manager. Brief landspout type tornado west of Norcross. No damage reported.

Relayed from emergency manager. Brief landspout type tornado northwest of Norcross. No damage reported.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

What forecasters said that day

The local office's own words before the tornado touched down, 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 tornado touched down at Aug 21, 2:35 PM CDT, 3 hours 43 minutes earlier. Its key messages:

  • There is a 2 of 5 risk for severe thunderstorms this afternoon and evening across portions of the area. Hazards could include damaging wind gusts to 75 mph, large hail up to the size of golf balls, and perhaps an isolated tornado.
Area forecast discussion, Aug 21, 2:35 PM CDT, 3 hours 43 minutes before
Area Forecast Discussion
National Weather Service Grand Forks ND
235 PM CDT Thu Aug 21 2025

.KEY MESSAGES...

- There is a 2 of 5 risk for severe thunderstorms this afternoon
  and evening across portions of the area. Hazards could include
  damaging wind gusts to 75 mph, large hail up to the size of
  golf balls, and perhaps an isolated tornado.

&&

.DISCUSSION...
Issued at 235 PM CDT Thu Aug 21 2025

...Synopsis...

Ridging continues to retreat southwest this afternoon, with H5
troughing extending southward from an upper low, situated over
Saskatchewan and Manitoba. Scattered showers and thunderstorms are
expected to continue through the afternoon and early evening, with
severe thunderstorms possible. A cold front traverses the area
tonight into Friday morning, with much cooler and drier weather
expected as we head into Friday afternoon and into the weekend. Look
for highs in the 70s on Friday, with breezy west winds, then in the
60s for Saturday and Sunday with breezy northwest to north winds.
Lows could fall into the low 40s Sunday night, with cooler spots
possibly seeing upper 30s. Slightly warmer temperatures return on
Tuesday as highs climb into the lower to middle 70s.

...Severe Thunderstorms this Afternoon and Evening...

There is a conditional chance for scattered severe thunderstorms
this afternoon and evening. Dew points have climbed into the upper
60s to near 70 degrees following a prefrontal trough. West of this
feature, instability is expected to climb upwards of 3500 J/Kg,
along with deep layer shear ranging from 30-40 knots. Low level flow
remains weak; however, near storm influences could allow low level
shear to be locally supportive of hybrid supercells and clusters.
Forcing is somewhat weak due to the lack of H5/H7 shortwave support
and most of the initiation is likely to occur just ahead of the cold
front, where the steepest theta-e gradients exist. Soundings
continue to support upscale growth, with line segments potentially
leading to damaging wind gusts as the afternoon progresses. DCAPE
values are in the range of 1100 to 1300 J/Kg, along with PW values
ranging from 1.3 to 1.7 inches. This should allow for moderate
precip loading into any updraft that is able to initiate. Wind gusts
of 75 mph are possible with today's strongest storms, along with
hail up to the size of golf balls. Tornado risk continues to be
present but overall generally low. Storm scale influences will play
the biggest role for tornado risk as hybrid clusters could show more
supercell characteristics in the presence of increased low level
shear from nearby outflow boundaries.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1239 PM CDT Thu Aug 21 2025

MVFR conditions prevail where showers and thunderstorms are
occurring this afternoon, with VFR conditions elsewhere. A cold
front continues to work to the southeast this afternoon,
bringing additional thunderstorm activity to most of the TAF
sites. A few storms could become severe, with wind gusts and
large hail being the primary risk. An isolated tornado cannot be
ruled out. Winds shift to the west and northwest this evening
following the frontal passage.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.

&&

DISCUSSION...Lynch
AVIATION...Lynch
Hazardous weather outlook, Aug 21, 5:28 PM CDT, 50 minutes before
Hazardous Weather Outlook
National Weather Service Grand Forks ND
528 PM CDT Thu Aug 21 2025

MNZ004-007-NDZ007-008-016-026>030-038-049-052-054-222230-
Kittson-West Marshall-Cavalier-Pembina-Eastern Walsh-Nelson-
Grand Forks-Griggs-Steele-Traill-Barnes-Ransom-Sargent-
Western Walsh-
528 PM CDT Thu Aug 21 2025

This hazardous weather outlook is for portions of eastern North
Dakota and northwest Minnesota.

.DAY ONE...Tonight

There is a level 1 out of 5 risk for severe thunderstorms this
afternoon and evening for northeast North Dakota and northwest
Minnesota and late afternoon and evening southeast North Dakota
and west central Minnesota. The main hazards will be potential for
wind gusts to 75 mph and hail to golf ball size.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be required today.

NDZ006-014-015-024-222230-
Towner-Benson-Ramsey-Eddy-
528 PM CDT Thu Aug 21 2025

This hazardous weather outlook is for portions of eastern North
Dakota.

.DAY ONE...Tonight

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated today.

MNZ001>003-005-006-008-009-013>017-022>024-027>032-040-NDZ039-053-
222230-
West Polk-Norman-Clay-Roseau-Lake Of The Woods-East Marshall-
North Beltrami-Pennington-Red Lake-East Polk-North Clearwater-
South Beltrami-Mahnomen-South Clearwater-Hubbard-West Becker-
East Becker-Wilkin-West Otter Tail-East Otter Tail-Wadena-Grant-
Cass-Richland-
528 PM CDT Thu Aug 21 2025

This hazardous weather outlook is for portions of eastern North
Dakota, west central and northwest Minnesota.

.DAY ONE...Tonight

There is a level 2 out of 5 risk for severe thunderstorms this
afternoon and evening for southeast North Dakota and northwest
Minnesota and late afternoon and evening southeast North Dakota
and west central Minnesota. The main hazards will be potential for
wind gusts to 75 mph and hail to golf ball size. There is a low a
low probability for isolated tornadoes.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be required today.

In the hours before

Local storm report, Aug 21, 5:46 PM CDT, 32 minutes before
Preliminary Local Storm Report
National Weather Service Grand Forks ND
546 PM CDT Thu Aug 21 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0529 PM     Tornado          5 WSW Lamars            45.94N 96.78W
08/21/2025                   Richland           ND   Trained Spotter

            Observed tornado riding the North
            Dakota/South Dakota state line.

&&
Local storm report, Aug 21, 5:52 PM CDT, 26 minutes before
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The air that afternoon

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Aberdeen, SD (KABR), 12:00Z

11.3 hours before the tornado, 200 km from the path. August 21, 2025.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 12:00Z on 2025-08-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1155 joules per kilogram, CIN -351, lifted condensation level 1022 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Aberdeen, SD at 12:00Z on 2025-08-21The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 194 square meters per square second, 0 to 6 km bulk shear 25 knots.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. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
1155 J/kg
Mixed-layer CIN
-351 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1022 m above ground
0-6 km bulk shear
25 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
194 m²/s²
0-3 km storm-relative helicity
194 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3
0-3 km lapse rate
3.1 K/km

Open this sounding in Storm Lab

Aberdeen, SD (KABR), 00:00Z

0.7 hours after it, 200 km from the path. August 22, 2025.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 00:00Z on 2025-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2017 joules per kilogram, CIN -96, lifted condensation level 1254 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Aberdeen, SD at 00:00Z on 2025-08-22The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity -42 square meters per square second, 0 to 6 km bulk shear 47 knots.19395878Sfc1 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. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
2017 J/kg
Mixed-layer CIN
-96 J/kg
Surface CAPE
6217 J/kg
Mixed-layer LCL
1254 m above ground
0-6 km bulk shear
47 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
-42 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
-0.3
Supercell composite
-6.1
0-3 km lapse rate
6.7 K/km

Open this sounding in Storm Lab

The surface observations

Elbow Lake (Y63), 23 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:00 UTC

From the Iowa Environmental Mesonet's archive of airport observations.

The radar

The Aberdeen radar (KABR), 175 km away, was scanning. The volume nearest the touchdown began at 23:20 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

This ground now

The live radar over the trackEvery 2025 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

The other tornadoes of August 21, 2025

2 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 215:29 PM CDTEF1Richland, ND1.830
August 216:18 PM CDTUnratedGrant, MN0.330

What this means

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.