Tornadoes · United States · Minnesota · 2009

EF0 tornado, Elrosa, Minnesota, July 14, 2009

This EF0 tornado ran 0.0 miles across Stearns County on July 14, 2009, touching down at 5:07 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
July 14, 2009
Touchdown
5:07 PM CDT (22:07 UTC)
Path length
0.0 miles (0.1 km)
Path width
20 yards (18 m)
Deaths
0
Injuries
0
County
Stearns County
Touchdown point
45.583, -94.988
Lift-off point
45.583, -94.988
Record number
0907141607-01

What the Weather Service recorded

A strong cold front, deep moisture and a high shear environment led to severe weather across portions of central Minnesota late Tuesday afternoon and evening of July 14th. Several individual storms developed across west central Minnesota and moved quickly northeast and spawned three tornadoes near Swift Falls, Elrosa and Spicer, Minnesota. In addition, several strong thunderstorms tracked across northern Todd and far northwestern Morrison County where two to four inches of rain fell in a short period of time. Due to the highly moist environment, and high rainfall rates, several areas of urban flooding was reported. One was in the community of Staples, and another was in St. Cloud.

Brief touchdown in an open field was videotaped by a trained spotter and viewed by multiple eyewitnesses.

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

The warnings

23 minutes of warning. NWS MPX issued a tornado warning for this county at 21:44 UTC, 23 minutes before the tornado touched down, in force until 22:30 UTC.

The county was under a severe thunderstorm watch, issued at 19:41 UTC and running to 02:00 UTC.

Issued (UTC)ExpiredProductOffice
19:41 UTC02:00 UTCSevere Thunderstorm WatchMPX
21:36 UTC22:15 UTCSevere Thunderstorm WarningMPX
21:44 UTC22:30 UTCTornado WarningMPX
21:48 UTC22:30 UTCTornado WarningMPX
22:00 UTC22:45 UTCTornado WarningMPX
22:32 UTC23:00 UTCTornado WarningMPX
23:11 UTC00:03 UTCSevere Thunderstorm WarningMPX
23:18 UTC23:32 UTCTornado WarningMPX
23:41 UTC03:30 UTCFlood WarningMPX

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The forecast that day

The Storm Prediction Center had this point in a Slight Risk, with a 0.05 chance of a tornado within 25 miles. 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.

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

10.1 hours before the tornado, 136 km from the path. July 14, 2009.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2009-07-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 35 joules per kilogram, CIN -90, lifted condensation level 1035 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2009-07-14The 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 108 square meters per square second, 0 to 6 km bulk shear 23 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
35 J/kg
Mixed-layer CIN
-90 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1035 m above ground
0-6 km bulk shear
23 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
178 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6
0-3 km lapse rate
5.1 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 00:00Z

1.9 hours after it, 136 km from the path. July 15, 2009.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2009-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 548 joules per kilogram, CIN -235, lifted condensation level 917 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2009-07-15The 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 396 square meters per square second, 0 to 6 km bulk shear 52 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
548 J/kg
Mixed-layer CIN
-235 J/kg
Surface CAPE
1165 J/kg
Mixed-layer LCL
917 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
29 kt
0-1 km storm-relative helicity
396 m²/s²
0-3 km storm-relative helicity
458 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4
0-3 km lapse rate
5.7 K/km

Open this sounding in Storm Lab

The surface observations

Glenwood (GHW), 27 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
20:14 UTC75.266.2150° 14 kt231006.4
20:33 UTC75.266.2160° 14 kt241005.8-VCTSRA
20:53 UTC73.466.2150° 20 kt261005.1-VCTSRA
21:13 UTC73.468160° 12 kt221005.1RA
21:34 UTC75.269.8170° 14 kt181005.1-DZ
21:53 UTC75.266.2170° 14 kt181004.7
22:13 UTC75.269.8180° 9 kt1004.4
22:34 UTC78.869.8190° 12 kt171004.4VCTS
22:53 UTC78.869.8200° 13 kt171004.1
23:13 UTC7769.8210° 16 kt201004.1VCTS
23:33 UTC75.266.2250° 16 kt261004.7VCTS
23:53 UTC73.466.2260° 22 kt291005.1

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

The radar

The Minneapolis radar (KMPX), 138 km away, was scanning. The volume nearest the touchdown began at 22:06 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
21:15 UTCFUNNEL CLOUD4 Ne BensonSwift, MN
21:21 UTCTORNADO3 Se Swift FallsSwift, MNAN NWS STORM SURVEY AND VISUAL REPORTS CONFIRM A TORNADO FROM 3 MILES SOUTHWEST OF SWIFT FALLS TO 6 MILES NORTHWEST OF SWIFT FALLS. MAXIMUM DAMAGE WAS EF-2 WITH ESTIMATED WINDS 110-119 MPH. TORNADO DAMAGE INCLUDED DESTRU
21:21 UTCTORNADO3 Sw Swift FallsSwift, MNAN NWS STORM SURVEY AND VISUAL REPORTS CONFIRM A TORNADO FROM 3 MILES SOUTHWEST OF SWIFT FALLS TO 6 MILES NORTHWEST OF SWIFT FALLS. MAXIMUM DAMAGE WAS EF-2 WITH ESTIMATED WINDS 110-119 MPH. TORNADO DAMAGE INCLUDED DESTRU
21:23 UTCTORNADO4 Sw GilchristPope, MNSPOTTER REPORTED TORNADO ON THE GROUND
21:36 UTCTORNADO6 Nne Swift FallsPope, MNTORNADO REPORTED NEAR SCANDINAVIAN LAKE
21:40 UTCTORNADOSpicerKandiyohi, MNLAW ENFORCEMENT REPORTED A TORNADO ON THE GROUND IN SPICER WITH DEBRIS SEEN AT A LOCAL SHOPPING MALL.
21:41 UTCTORNADO2 Sw SpicerKandiyohi, MNAN NWS STORM SURVEY...VISUAL REPORTS...AND VIDEO CONFIRMED A TORNADO FROM TWO MILES SOUTHWEST OF DOWNTOWN SPICER TO APPROXIMATELY FOUR MILES EAST NORTHEAST OF DOWNTOWN SPICER. MAXIMUM DAMAGE WAS EF-1 WITH ESTIMATED WINDS
21:50 UTCTORNADO3 Ne SpicerKandiyohi, MNTORNADO TRACKED ACROSS GREEN LAKE
21:53 UTCTSTM WND DMG4 E SpicerKandiyohi, MNAN NWS STORM SURVEY FOUND STRAIGHT-LINE THUNDERSTORM WIND DAMAGE ASSOCIATED WITH THE REAR-FLANK DOWNDRAFT OF THE TORNADIC THUNDERSTORM WHICH WENT THROUGH SPICER. LOCALIZED EXTENSIVE TREE DAMAGE WAS FOUND. ESTIMATED WINDS
22:52 UTCFUNNEL CLOUD2 E RichmondStearns, MN
00:15 UTCHEAVY RAIN 2.8St JosephStearns, MNRECIEVED 2.8 INCHES OF RAIN FROM AFTERNOON THUNDERSTORMS.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2009 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

The other tornadoes of July 14, 2009

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 144:21 PM CDTEF2Swift, MN7.9350$500,000
July 144:41 PM CDTEF1Kandiyohi, MN6.4250$250,000
July 146:52 PM CDTEF0Ford, KS0.430

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.