Tornadoes · United States · Michigan · 2017

EF1 tornado, Browne Center to Clarksville, Michigan, April 10, 2017

From Browne Center to Clarksville, this EF1 tornado ran 5.3 miles across Ionia and Kent counties on April 10, 2017, touching down at 8:36 PM EDT and reaching 220 yards wide. It killed nobody, and did $210,000 of property damage.

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 mphthis tornado

    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
EF1
Date
April 10, 2017
Touchdown
8:36 PM EDT (00:36 UTC)
Lifted
8:41 PM EDT (00:41 UTC)
On the ground
5 minutes
Path length
5.3 miles (8.6 km)
Path width
220 yards (201 m)
Deaths
0
Injuries
0
Property damage
$210,000
Counties
Ionia and Kent counties
Touchdown point
42.784, -85.367
Lift-off point
42.817, -85.272
Record number
1704101836-01

The damage survey

11 damage points were recorded along this path by NWS GRR, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 90 mph.

  • Metal roofing off barn. Section of this roofing carried abour 0.6 miles east-northeast and landed in field.
  • Section of roof carried 0.6 miles to east-northeast
  • Metal roofing loffted into tree branches. Windows broken.
  • Above ground pool decking destroyed. Barn lost about half of of roof. Doors blown in.

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

What the Weather Service recorded

An isolated EF1 tornado developed over extreme southeastern Kent county during the evening hours of April 10th. Dozens of large trees were snapped or uprooted and three barns were heavily damaged. The damage began on 100th St just east of Alden Nash Ave and then continued to the east-northeast, crossing Wingeier Ave where a barn lost metal roofing. One metal section was carried 0.6 miles by the tornado and landed in a field. ||The tornado damage intensified as the funnel narrowed and crossed 92nd St in the vicinity of the Tyler Creek Golf Course, where a swath of trees were snapped and uprooted. Peak winds in this area were estimated at 90 mph. The tornado crossed Freeport Ave and Keim Road. It then crossed Hastings Road with peak winds estimated around 65 mph, taking down large tree limbs. The damage ended around Bell Road north of Keim Road. There were also isolated reports of large hail and wind damage across portions of western lower Michigan.

An NWS storm survey confirmed that an EF1 tornado occurred with peak winds of 90 mph and a path width of 220 yards. Dozens of large trees were blown down and there was significant damage to several outbuildings.

An EF1 tornado over extreme southeastern Kent county continued to move east northeast into far southwestern Ionia county. It took down several tree limbs before dissipating.

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 Rapids, MI wrote its last area forecast discussion before the tornado touched down at Apr 10, 7:45 PM EDT, 51 minutes earlier.

Area forecast discussion, Apr 10, 7:45 PM EDT, 51 minutes before
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Hazardous weather outlook, Apr 10, 11:07 AM EDT, 9 hours 29 minutes before
HAZARDOUS WEATHER OUTLOOK
National Weather Service Grand Rapids MI
1107 AM EDT Mon Apr 10 2017

MIZ037>040-043>046-050>052-056>059-064>067-071>074-110830-
Mason-Lake-Osceola-Clare-Oceana-Newaygo-Mecosta-Isabella-Muskegon-
Montcalm-Gratiot-Ottawa-Kent-Ionia-Clinton-Allegan-Barry-Eaton-
Ingham-Van Buren-Kalamazoo-Calhoun-Jackson-
1107 AM EDT Mon Apr 10 2017

This hazardous weather outlook is for portions of southwest Lower
Michigan.

.DAY ONE...This Afternoon and Tonight

Strong to severe thunderstorms are possible between 400 pm and
Midnight. The storms will be capable of damaging winds, large hail
to around 1 inch in diameter and locally heavy rain. An isolated
tornado cannot be ruled out either.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed from mid afternoon through midnight.

LMZ844>849-110830-
St Joseph to South Haven MI-South Haven to Holland MI-
Holland to Grand Haven MI-Grand Haven to Whitehall MI-
Whitehall to Pentwater MI-Pentwater to Manistee MI-
1107 AM EDT Mon Apr 10 2017

This hazardous weather outlook is for portions of southwest Lower
Michigan.

.DAY ONE...This Afternoon and Tonight

Winds and waves will pose a hazard to smaller craft today. Winds
and waves will be locally higher in and near thunderstorms.

Morning storms have exited, but more storms are in the forecast from
mid afternoon through this evening. Wind gusts in excess of 35
knots, large hail and cloud to water lightning strikes are all
possible with the strongest storms.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed from mid afternoon through
midnight.

Meade

In the hours before

Special weather statement, Apr 10, 8:02 PM EDT, 34 minutes before
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Local storm report, Apr 10, 8:10 PM EDT, 26 minutes before
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Special weather statement, Apr 10, 8:26 PM EDT, 10 minutes before
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Local storm report, Apr 10, 8:28 PM EDT, 8 minutes before
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Local storm report, Apr 10, 8:31 PM EDT, 5 minutes before
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Local storm report, Apr 10, 8:34 PM EDT, 2 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.

Detroit, MI (KDTX), 00:00Z

0.6 hours before the tornado, 155 km from the path. April 11, 2017.

Skew-T log-pSkew-T log-p diagram, Detroit, MI at 00:00Z on 2017-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 88 joules per kilogram, CIN -57, lifted condensation level 1361 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, Detroit, MI at 00:00Z on 2017-04-11The 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 79 square meters per square second, 0 to 6 km bulk shear 45 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
88 J/kg
Mixed-layer CIN
-57 J/kg
Surface CAPE
522 J/kg
Mixed-layer LCL
1361 m above ground
0-6 km bulk shear
45 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
137 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

The surface observations

Grand Rapids (GRR), 19 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 Grand Rapids radar (KGRR), 21 km away, was scanning. The volume nearest the touchdown began at 00:37 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 2017 tornado in MichiganEvery tornado in Michigan since 1950Warnings in force in Michigan nowThe forecast where you are

The other tornadoes of April 10, 2017

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 107:10 PM CDTEF1Smith, TX0.5100
April 107:35 PM CDTEF1Smith, TX1.8250$25,000
April 1010:45 PM CDTEF0McLennan, TX0.780$40,000

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.