Tornadoes · United States · Minnesota · 2026

Unrated tornado, Bigelow to Org, Minnesota, May 17, 2026

Name: Unrated tornado, Bigelow to Org, Minnesota, May 17, 2026
Start: 2026-05-17T22:58:00.000Z
End: 2026-05-17T23:00:00.000Z
Location: Bigelow to Org, Minnesota

From Bigelow to Org, this Unrated tornado ran 1.3 miles across Nobles County on May 17, 2026, touching down at 5:58 PM CDT and reaching 25 yards wide. It killed nobody.

Preliminary. This is NWS FSD's damage survey, filed in the Damage Assessment Toolkit. The rating, the path and the casualties are the survey's and can change while it is revised. The Storm Prediction Center compiles the official record of 2026 from these surveys and publishes it in the spring of 2027; this page moves to that tornado's permanent address when it does.

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.

EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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 survey

Rating, as surveyed: Unrated, preliminary
Date: May 17, 2026
Touchdown: 5:58 PM CDT (22:58 UTC)
Lifted: 6:00 PM CDT (23:00 UTC)
On the ground: 2 minutes
Path length: 1.3 miles (2.0 km)
Path width: 25 yards (23 m)
Deaths: 0
Injuries: 0
County: Nobles County
Touchdown point: 43.535, -95.804
Lift-off point: 43.540, -95.780
Surveyed by: NWS FSD
Survey last edited: July 31, 2026
Record number: None yet. SPC numbers 2026 in the spring of 2027.

What the survey found

Brief tornado in an open field reported by public. No known damage. Location is an approximation based on video evidence.

Written by NWS FSD in the NWS Damage Assessment Toolkit. A survey is revised as better evidence arrives.

What the Weather Service recorded

An approaching mid-level disturbance broke a weak cap and allowed storms to erupt during the afternoon along a slow moving frontal boundary. These storms rapidly organized into short bowing segments and then became highly linear across northwest Iowa and southwest Minnesota during the evening. Initial supercell storms produced large hail with as much as 2000-3000 J/kg MLCAPE, but DCAPE of around 750-1000 J/kg allowed for the development of organized cold pools and an increasing wind threat. Several brief and highly visible tornadic spin-ups developed along the line of storms by late afternoon and evening across far eastern South Dakota, northwest Iowa and southwest Minnesota.

A brief tornado occurred in an open field around 6 miles south of Rushmore. The tornado was estimated to touch down around one-half mile northwest of the intersection of 320th Street and Jones Avenue. The tornado tracked northeast for less than two minutes across open fields before lifting south of 310th Street west of King Avenue. There were no damage indicators present to derive a rating. The average path width was estimated at 25 yards based on video evidence.

A trained spotter observed a very brief tornado in an open field southwest of Worthington. The tornado was estimated to touch down just east of Oliver Avenue around one-half mile north of 280th Street. The tornado tracked northeast in open fields for less than one minute before lifting near South Crailsheim Road. There were no damage indicators present to derive a rating. The average path width was estimated at 20 yards.

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

The forecast that day

The Storm Prediction Center had this point in a Enhanced Risk, with a 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 20:02 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

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 Sioux Falls, SD wrote its last area forecast discussion before the tornado touched down at May 17, 1:20 PM CDT, 4 hours 38 minutes earlier. Its key messages:

There is high confidence that severe thunderstorms will develop this afternoon and evening, producing large hail, destructive straight-line winds, and a few tornadoes. An Enhanced Risk (level 3 of 5) of severe storms is in place.
A transitioning storm mode will shift hazards from large hail and tornadoes initially, to widespread wind damage as an intense line of storms tracks east of Interstate 29 this evening.
A lower risk of severe weather exists late Monday afternoon and evening, mainly over northwest IA, before quieter weather moves in for the mid-week period.

Area forecast discussion, May 17, 1:20 PM CDT, 4 hours 38 minutes before

Area Forecast Discussion
National Weather Service Sioux Falls SD
Issued by National Weather Service Lincoln IL
120 PM CDT Sun May 17 2026

.KEY MESSAGES...

- There is high confidence that severe thunderstorms will
  develop this afternoon and evening, producing large hail,
  destructive straight-line winds, and a few tornadoes. An
  Enhanced Risk (level 3 of 5) of severe storms is in place.

- A transitioning storm mode will shift hazards from large hail
  and tornadoes initially, to widespread wind damage as an
  intense line of storms tracks east of Interstate 29 this
  evening.

- A lower risk of severe weather exists late Monday afternoon
  and evening, mainly over northwest IA, before quieter weather
  moves in for the mid-week period.

&&

.DISCUSSION...
Issued at 120 PM CDT Sun May 17 2026

The short-term convective outlook presents a highly volatile
spring severe weather setup. Latest surface analysis shows a
complex pattern, anchored by a strong 994 mb low over northwest
KS. An inverted trough extended north of the low through
central SD, while a well-defined warm front stretched northeast
of the low into east central NE. A weaker low was also noted in
north central NE. Visible satellite imagery revealed stable
wave clouds advancing northeast over far northeast NE and
extreme SE SD, ahead of the advancing warm front. Regional
radar imagery showed a complex of strong to severe storms over
north central NE. This storm complex is forecast by short range
guidance to continue tracking east this afternoon, intensifying
as interacts with the richer low- level moisture pool near and
south of the warm front.

Moderate to strong instability will be in place over the
southern to eastern CWA by late afternoon with MLCAPE nearing
3000 J/kg. In addition, deep layer shear will increase to around
50 kt, coincident with a mid level speed max ejecting from the
deep upper trough to our west. As the system evolves over the
next several hours, it appears the ingredients for a significant
severe weather event will be most favored over the southern to
eastern CWA. Ahead of the main convective line, some CAMs show
supercell development along the northward advancing warm front.
These storms would present a risk of very large hail (2"+) and
tornadoes. Given the amount of low level SRH/curved hodographs
present, a couple strong tornadoes are possible. The convective
cluster currently entering our far southwest CWA should
strengthen as it shifts east, with an initial hail and tornado
threat transitioning to a damaging straight line wind threat
(70+ MPH) as it grows upscale into a squall line/QLCS. Some
line-embedded QLCS tornadoes are possible, especially for any
line segments that become oriented north/south or
northwest/southeast, given southwesterly 0-3 km shear vectors.
Timing from latest high-res guidance suggests this activity
exits to the east of our CWA late this evening.

Precipitation amounts will vary significantly based on convective
tracks, though NBM guidance and HREF probability match mean
fields project a widespread 0.50 to 1.50 inches of rainfall,
particularly across northwest Iowa and southwest Minnesota. On
Monday, the cold front finally pushes into the area. Instability
and shear are forecast to be much lower than today, however,
there will be a conditional risk of severe storms over the
eastern CWA during the late afternoon to evening, if the airmass
can destabilize sufficiently ahead of the front. SPC's Day 2
outlook indicates as Marginal Risk (level 1 of 5), for our MN
and IA counties.

Behind the departing upper wave, quasi-zonal flow sets up for
Tuesday and Wednesday, yielding quiet conditions and seasonally
cool high temperatures moderating from the upper 50s Tuesday to
mid-upper 60s Wednesday.

The next upper wave moves in for the Thursday to Friday period,
however Gulf moisture remains cutoff ahead of this system.
Evaluating the ECMWF Extreme Forecast Index (EFI) reveals no
significant climatological anomalies for precipitation or wind
across the upper Midwest during this period, reinforcing the
the idea of a low-impact system for our area. The current
forecast sticks closely to the NBM consensus, maintaining broad
20-30 percent probabilities for light rain for late Thursday
into Saturday.

By late this week and especially this weekend, temperatures
will embark on a steady upward trajectory, as the mid level flow
backs west, then southwest. The Climate Prediction Center (CPC)
6-10 day outlook favors above-normal temperatures across the
Northern Plains and Upper Midwest, which supports blended
guidance high temperatures reaching well into the 80s on
Sunday.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1248 PM CDT Sun May 17 2026

Showers and storms move through the region this afternoon into
tonight. Intermittent MVFR/IFR conditions will be possible throughout
this timeframe, especially in heavier rain. TSRA was included at
least in PROB30 groups, but is expected to be the dominant weather
type at times. Widespread MVFR/IFR cigs setting in overnight for much
of Monday.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.

&&

DISCUSSION...ILX/25
AVIATION...DYE

Hazardous weather outlook, May 17, 1:29 PM CDT, 4 hours 29 minutes before

Hazardous Weather Outlook
National Weather Service Sioux Falls SD
Issued by National Weather Service Lincoln IL
129 PM CDT Sun May 17 2026

IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ038>040-050-052>071-181830-
Lyon-Osceola-Dickinson-Sioux-O'Brien-Clay-Plymouth-Cherokee-
Buena Vista-Woodbury-Ida-Lincoln-Murray-Cottonwood-Nobles-Jackson-
Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury-Brookings-Gregory-
Jerauld-Sanborn-Miner-Lake-Moody-Brule-Aurora-Davison-Hanson-McCook-
Minnehaha-Charles Mix-Douglas-Hutchinson-Turner-Bon Homme-Yankton-
Union-
129 PM CDT Sun May 17 2026

This Hazardous Weather Outlook is for northwest Iowa, west central
Iowa, southwest Minnesota, northeast Nebraska, central South
Dakota, east central South Dakota, south central South Dakota and
southeast South Dakota.

.DAY ONE...This afternoon and tonight.

A significant severe weather event is possible this afternoon and
evening. Very large hail, damaging wind gusts, and tornadoes are all
possible. If you have outdoor plans know where your nearest shelter
is located. Please ensure you have multiple ways to receive warnings.
Have a plan to take shelter and act immediately if your area comes
under a severe weather warning.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Strong to severe storms are possible again Monday afternoon and
evening, particularly over northwest Iowa and southwest Minnesota.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed this afternoon and evening.

In the hours before

Local storm report, May 17, 5:42 PM CDT, 16 minutes before

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Local storm report, May 17, 5:44 PM CDT, 14 minutes before

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Local storm report, May 17, 5:47 PM CDT, 11 minutes before

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Local storm report, May 17, 5:52 PM CDT, 6 minutes before

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Local storm report, May 17, 5:54 PM CDT, 4 minutes before

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Local storm report, May 17, 5:55 PM CDT, 3 minutes before

Preliminary Local Storm Report
National Weather Service Sioux Falls SD
555 PM CDT Sun May 17 2026

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

0554 PM     Hail             Lismore                 43.75N 95.95W
05/17/2026  E1.75 Inch       Nobles             MN   Public

&&

TH

The surface observations

Worthington (OTG), 22 km from the path, in the two hours either side.

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

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

The radar

The Sioux Falls radar (KFSD), 76 km away, was scanning. The volume nearest the touchdown began at 22:55 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 track Every 2026 tornado in Minnesota Every tornado in Minnesota since 1950 Warnings in force in Minnesota now The forecast where you are

The other tornadoes of May 17, 2026

47 more have been surveyed in the United States that day, so far.

Date	Time	Rating	Where	Path (mi)	Width (yd)	Damage
May 17	3:17 PM EDT	EF0	Lee, FL	0.1	25
May 17	3:25 PM EDT	EF0	Lee, FL	2.1	150
May 17	3:35 PM EDT	EF0	Lee, FL	0.5	50
May 17	4:05 PM CDT	Unrated	Turner, SD	0.7	0
May 17	5:04 PM CDT	EF3	Howard, NE	6.1	350
May 17	5:23 PM CDT	EF0	Merrick, NE	1.3	30
May 17	6:15 PM CDT	Unrated	Nobles, MN	0.6	20
May 17	6:42 PM CDT	EF1	Thayer, NE	4.3	200	$10
May 17	7:11 PM CDT	EF0	Ida, IA	0.5	60
May 17	7:12 PM CDT	Unrated	Martin, MN	0.3	0
May 17	7:19 PM CDT	EF1	Thurston, NE	1.9	300
May 17	7:31 PM CDT	EF0	Woodbury, IA	2.5	75
May 17	7:37 PM CDT	EF1	Woodbury, IA	3.9	100
May 17	7:55 PM CDT	EF1	Saunders, NE	0.8	40
May 17	8:07 PM CDT	Unrated	Plymouth, IA	0.7	0
May 17	8:10 PM CDT	Unrated	Cherokee, IA	0.4	0
May 17	8:11 PM CDT	Unrated	Cherokee, IA	0.9	0
May 17	8:15 PM CDT	Unrated	Cherokee, IA	0.8	0
May 17	8:25 PM CDT	Unrated	Cherokee, IA	0.9	0
May 17	8:31 PM CDT	Unrated	Clay, IA	1.2	0
May 17	8:42 PM CDT	Unrated	Buena Vista, IA	2.2	75
May 17	8:45 PM CDT	EF1	Cass, NE	0.8	100
May 17	8:48 PM CDT	Unrated	Clay, IA	0.9	20
May 17	8:53 PM CDT	Unrated	Clay, IA	4.0	75
May 17	9:01 PM CDT	EF1	Calhoun, IA	4.2	50
May 17	9:03 PM CDT	EF1	Palo Alto, IA	3.5	25
May 17	9:05 PM CDT	EF1	Pocahontas, IA	1.1	25
May 17	9:06 PM CDT	EF0	Clay, IA	1.2	30
May 17	9:08 PM CDT	Unrated	Dickinson, IA	0.6	25
May 17	9:10 PM CDT	EF1	Palo Alto, IA	3.7	0
May 17	9:10 PM CDT	Unrated	Dickinson, IA	1.5	45
May 17	9:10 PM CDT	EF1	Calhoun, IA	0.2	30
May 17	9:12 PM CDT	Unrated	Emmet, IA	1.3	30
May 17	9:17 PM CDT	EF0	Palo Alto, IA	0.8	25
May 17	9:19 PM CDT	EF0	Palo Alto, IA	2.7	25
May 17	9:20 PM CDT	EF0	Palo Alto, IA	1.1	20
May 17	9:24 PM CDT	EF0	Webster, IA	4.7	50
May 17	9:29 PM CDT	EF1	Kossuth, IA	0.7	30
May 17	9:29 PM CDT	EF1	Emmet, IA	1.1	25
May 17	9:41 PM CDT	EF1	Kossuth, IA	10.2	0
May 17	10:07 PM CDT	EF1	Cerro Gordo, IA	0.2	40
May 17	10:10 PM CDT	EF1	Worth, IA	9.1	0
May 17	10:13 PM CDT	EF1	Cerro Gordo, IA	7.0	40
May 17	10:14 PM CDT	EF1	Freeborn, MN	1.2	0
May 17	10:15 PM CDT	Unrated	Cerro Gordo, IA	2.4	0
May 17	10:18 PM CDT	Unrated	Cerro Gordo, IA	2.6	0
May 17	10:27 PM CDT	EF1	Freeborn, MN	0.4	0

What this means

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. A survey can be revised, so the rating, the path and the casualties can all still change.

Sources

NWS Damage Assessment Toolkit, the record the survey teams file from the damage, and NOAA Storm Prediction Center storm reports. Neither is the official database for 2026, which SPC publishes in the spring of 2027.