Tornadoes · United States · Minnesota · 2014

EF0 tornado, Ottertail, Minnesota, June 20, 2014

This EF0 tornado ran 0.3 miles across Otter Tail County on June 20, 2014, touching down at 5:10 PM CDT and reaching 20 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 mphthis tornado

    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. Unrated

    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
EF0
Date
June 20, 2014
Touchdown
5:10 PM CDT (22:10 UTC)
Lifted
5:11 PM CDT (22:11 UTC)
On the ground
1 minutes
Path length
0.3 miles (0.5 km)
Path width
20 yards (18 m)
Deaths
0
Injuries
0
County
Otter Tail County
Touchdown point
46.413, -95.608
Lift-off point
46.415, -95.602
Record number
1406201610-01

What the Weather Service recorded

On the evening of June 20th, a slow moving upper level low pressure system was located over southern Saskatchewan. Strong upper level winds combined with a cold pool aloft to help generate scattered thunderstorms across the northwest quarter of Minnesota. Reports of large hail and funnel clouds were received.

A persistent funnel with an intermittent waterspout was seen over northeast Otter Tail Lake. The waterspout was evident for about a minute.

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 Jun 20, 2:24 PM CDT, 2 hours 46 minutes earlier.

Area forecast discussion, Jun 20, 2:24 PM CDT, 2 hours 46 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
224 PM CDT FRI JUN 20 2014

.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 225 PM CDT FRI JUN 20 2014

THE MAIN CHALLENGE WILL BE CONVECTIVE CHANCES AND TEMPS. MODELS
REMAIN IN DECENT AGREEMENT...WITH THE GFS INITIALIZING CURRENT
SITUATION WELL SO WILL UTILIZE.

FOR THE REST OF THIS AFTERNOON AND EVENING...A STRONG
SHORTWAVE/SPEED MAX WILL MOVE FROM WEST TO EAST. THERE WILL CAPES
AROUND 1500 J/KG ALONG AND MAINLY EAST OF THE VALLEY INTO THIS
EVENING. EXPECT SHOWERS AND STORMS...A FEW SEVERE MAINLY EAST OF
THE VALLEY THROUGH AROUND 00Z. THE MAIN THREATS WILL BE LARGE
HAIL...DAMAGING WINDS AND CAN/T RULE OUT AN ISOLATED TORNADO IF
SFC DEWPOINTS CAN POOL IN THE LOW/MID 60S NEAR WEAK SFC LOW THAT
WILL MOVE INTO MN LAKES COUNTRY.

ON SATURDAY...EXPECT A WARM DAY WITH TEMPS INTO THE MID 80S...AND
IT WILL FEEL LIKE THE FIRST DAY OF SUMMER. THERE WILL BE THE
CHANCE FOR A FEW AFTERNOON SHOWERS OR STORMS NEARLY ANYWHERE WITH
THE UPPER LOW SPINNING IN CANADA.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 225 PM CDT FRI JUN 20 2014

FOR SUNDAY...THE THREAT FOR SHOWERS AND STORMS SHOULD MOVE INTO
THE EASTERN AREAS BY AFTERNOON BEHIND A SFC COOL FRONT. TEMPS WILL
WARM TO AROUND 80 FOR MOST AREAS.

ON MONDAY...A SFC BOUNDARY/COOL FRONT WILL DROP SOUTH FROM
CANADA...AND EXPECT AFTERNOON SHOWERS AND STORMS. THE GFS IS QUITE
BULLISH WITH THIS POTENTIAL...BUT THE ECMWF IS MAINLY DRY. WILL
CONTINUE WITH THE POTENTIAL FOR AFTERNOON SHOWERS AND
STORMS...WITH THE BEST CHANCE IN THE NORTHERN VALLEY CLOSER TO
UPPER SUPPORT. TEMPS WILL BE A BIT COOLER ON MONDAY WITH MORE
CLOUDS AND SLIGHTLY COOLER TEMPS ALOFT.

FOR MON NIGHT THROUGH THU...MODELS IN GENERAL AGREEMENT AND USED A
BLENDED SOLN FOR THIS PACKAGE. UPPER LEVEL PATTERN BEGINS TO SHIFT
AS THE UPPER LOW OVER THE AREA FILLS AND LIFTS TO THE EAST. THE
UPPER RIDGE BEGINS TO SHIFT EAST ACROSS THE AREA...AND WILL BRING
WARMER TEMPERATURES TO THE REGION BY THE END OF THE PERIOD.
OTHERWISE...WILL SEE SOME IMPULSES MOVING THRU THE FLOW...BRINGING
PERIODIC CHANCES FOR -SHRA/-TSRA FOR THE AREA.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1254 PM CDT FRI JUN 20 2014

EXPECT VFR CONDITIONS THRU THE FORECAST PERIOD. OTHERWISE...MID
LEVEL CLOUDS WILL INCREASE ACROSS THE NORTHERN PART OF THE AREA AS
AN UPPER LEVEL DISTURBANCE CROSSES JUST SOUTH OF THE INTERNATIONAL
BORDER. LOOKING FOR MAINLY SHOWERS EARLY IN THE FCST PERIOD AS THE
UPPER DISTURBANCE MOVES EAST. HOWEVER...A GREATER RISK EXISTS FOR
SCATTERED TSTMS LATER THIS AFTERNOON...WITH A COMBINED INCREASE IN
SFC HEATING AND ENERGY ALOFT. WINDS ARE EXPECTED TO REMAIN GENERALLY
SOUTH TO SOUTHWEST AS SFC LOW PRESSURE CONTINUES TO AFFECT THE AREA.

&&

.HYDROLOGY...
ISSUED AT 1254 PM CDT FRI JUN 20 2014

RIVER FORECASTS ARE ON TRACK AS RISES CONTINUE AS A RESULT OF THE
RECENT RAINFALL. THE WILD RICE RIVER AT ABERCROMBIE IS NEARING
CREST WITHIN MODERATE FLOOD STAGE...AND FARGO AND OSLO ON THE RED
RIVER ARE EXPECTED TO REACH MODERATE FLOOD STAGE. THE FLOOD
WARNING ON THE BUFFALO RIVER AT HAWLEY HAS BEEN CANCELLED AS
CURRENT FORECASTS INDICATE GRADUALLY FALLING STAGES. NO OTHER
SIGNIFICANT CHANGES WERE MADE TO FORECAST POINTS. AN AREAL FLOOD
WARNING REMAINS IN EFFECT FOR EAST CENTRAL BELTRAMI COUNTY WITH
THE TAMARAC RIVER OUT OF ITS BANKS NEAR WASKISH.

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

SHORT TERM...DK
LONG TERM...HOPKINS/DK
AVIATION...HOPKINS
HYDROLOGY...MAKOWSKI
Hazardous weather outlook, Jun 20, 5:59 AM CDT, 11 hours 11 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND FORKS ND
559 AM CDT FRI JUN 20 2014

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-211100-
WEST POLK-NORMAN-CLAY-KITTSON-ROSEAU-LAKE OF THE WOODS-
WEST MARSHALL-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-TOWNER-CAVALIER-
PEMBINA-BENSON-RAMSEY-EASTERN WALSH-EDDY-NELSON-GRAND FORKS-
GRIGGS-STEELE-TRAILL-BARNES-CASS-RANSOM-SARGENT-RICHLAND-
WESTERN WALSH-
559 AM CDT FRI JUN 20 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN NORTH
DAKOTA...WEST CENTRAL AND NORTHWEST MINNESOTA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS WILL BEGIN TO DEVELOP ACROSS THE REGION THIS
AFTERNOON...WITH A SLIGHT CHANCE OF A FEW STORMS IN WEST CENTRAL
MINNESOTA BECOMING SEVERE. HAIL AND DAMAGING WINDS WILL BE THE
PRIMARY THREAT THROUGH THE AFTERNOON AND EVENING...MAINLY SOUTH
AND EAST OF A MOORHEAD TO BEMIDJI LINE. A STRONG UPPER LEVEL
STORM SYSTEM MOVING INTO THE AREA WILL HELP STORMS DEVELOP...AND
THINK THAT THERE WILL BE ENOUGH SUNSHINE FOR A WHILE TODAY TO MAKE
THE ATMOSPHERE UNSTABLE AND STRONG TO SEVERE STORMS POSSIBLE.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

AFTERNOON THUNDERSTORMS ARE POSSIBLE. THE POTENTIAL FOR SEVERE
STORMS IS FAIRLY LOW...BUT NOT IMPOSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON IN PORTIONS OF
WEST CENTRAL MINNESOTA.

In the hours before

Local storm report, Jun 20, 4:32 PM CDT, 38 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
432 PM CDT FRI JUN 20 2014

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

0430 PM     FUNNEL CLOUD     ERHARD                  46.48N 96.10W
06/20/2014                   OTTER TAIL         MN   TRAINED SPOTTER

            ROTATION EVIDENT NEAR ERHARD AS VIEWED FROM WEST OF TOWN.

&&

GGUST
Local storm report, Jun 20, 4:51 PM CDT, 19 minutes before
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Local storm report, Jun 20, 4:54 PM CDT, 16 minutes before
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Local storm report, Jun 20, 4:55 PM CDT, 15 minutes before
PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
455 PM CDT FRI JUN 20 2014

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

0454 PM     HAIL             6 NNW STAR LAKE         46.61N 95.85W
06/20/2014  E0.88 INCH       OTTER TAIL         MN   LAW ENFORCEMENT

            DIME TO NICKEL SIZED HAIL AT INTERSECTION OF CR108 AND
            CR41.

&&

GGUST
Local storm report, Jun 20, 5:02 PM CDT, 8 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
502 PM CDT FRI JUN 20 2014

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

0500 PM     HAIL             STAR LAKE               46.53N 95.81W
06/20/2014  M0.88 INCH       OTTER TAIL         MN   TRAINED SPOTTER

            HAIL FOR LAST FEW MINUTES WITH VERY HEAVY RAIN. HAIL AN
            INCH OR MORE DEEP ACROSS THE YARDS.

&&

GGUST
Local storm report, Jun 20, 5:06 PM CDT, 4 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
506 PM CDT FRI JUN 20 2014

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

0505 PM     FUNNEL CLOUD     4 W OTTERTAIL           46.43N 95.64W
06/20/2014                   OTTER TAIL         MN   LAW ENFORCEMENT

            PERSISTENT WALL CLOUD AND POSSIBLE FUNNEL OVER WALKER
            LAKE... ABOUT 4W OF THE TOWN OF OTTERTAIL.

&&

GGUST

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.

Minneapolis, MN (KMPX), 12:00Z

10.2 hours before the tornado, 234 km from the path. June 20, 2014.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2014-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 301 joules per kilogram, CIN -98, lifted condensation level 689 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, Minneapolis, MN at 12:00Z on 2014-06-20The 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 32 square meters per square second, 0 to 6 km bulk shear 32 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
301 J/kg
Mixed-layer CIN
-98 J/kg
Surface CAPE
1119 J/kg
Mixed-layer LCL
689 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 00:00Z

1.8 hours after it, 234 km from the path. June 21, 2014.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2014-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -88180, lifted condensation level 3130 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Minneapolis, MN at 00:00Z on 2014-06-21The 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 142 square meters per square second, 0 to 6 km bulk shear 46 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
0 J/kg
Mixed-layer CIN
-88180 J/kg
Surface CAPE
795 J/kg
Mixed-layer LCL
3130 m above ground
0-6 km bulk shear
46 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
142 m²/s²
0-3 km storm-relative helicity
290 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4
0-3 km lapse rate
7.9 K/km

Open this sounding in Storm Lab

The surface observations

Wadena Municipal (ADC), 30 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 Fargo/Grand Forks radar (KMVX), 180 km away, was scanning. The volume nearest the touchdown began at 22:09 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 2014 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

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.