Tornadoes · United States · Idaho · 1991

F2 tornado, Bonner County, Idaho, April 9, 1991

This F2 tornado ran 1.0 miles across Bonner County on April 9, 1991, touching down at 6:15 PM PDT and reaching 100 yards wide. It killed nobody, and did $50,000 to $500,000 of property damage.

The rating scale

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

  1. F040 to 72 mph

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

  2. F173 to 112 mph

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

  3. F2113 to 157 mphthis tornado

    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. F3158 to 206 mph

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

  5. F4207 to 260 mph

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

  6. F5261 to 318 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
F2
Date
April 9, 1991
Touchdown
6:15 PM PDT (01:15 UTC)
Path length
1.0 miles (1.6 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
0
Property damage
$50,000 to $500,000
County
Bonner County
Touchdown point
48.180, -116.900
Record number
222

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

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.

This ground now

The live radar over the trackEvery 1991 tornado in IdahoEvery tornado in Idaho since 1950Warnings in force in Idaho nowThe forecast where you are

The other tornadoes of April 9, 1991

24 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 911:00 AM CDTF0Madison, TN0.310$500 to $5,000
April 912:50 PM CDTF2Todd, KY18.0300$500,000 to $5 million
April 91:45 PM CDTF2Barren, KY0.54003$500,000 to $5 million
April 92:45 PM EDTF1Kenton, KY3.0100$50,000 to $500,000
April 93:00 PM EDTF1Madison, KY4.050$5,000 to $50,000
April 93:00 PM EDTF1Rockcastle, KY2.0100$50,000 to $500,000
April 93:45 PM EDTF0Chautauqua, NY0.510$5,000 to $50,000
April 94:15 PM EDTF1Erie, NY0.510$5,000 to $50,000
April 95:30 PM EDTF1Livingston, NY0.530$50,000 to $500,000
April 92:50 PM PDTF0Kitsap, WA0.830$5,000 to $50,000
April 96:20 PM EDTF0Braxton, WV0.140$500 to $5,000
April 94:30 PM PDTF0Multnomah, OR0.210$50 to $500
April 98:15 PM EDTF0Brevard, FL0.110
April 98:30 PM EDTF1Westmoreland, PA0.2504$5,000 to $50,000
April 98:40 PM EDTF1Bedford, PA0.5100$5,000 to $50,000
April 98:40 PM EDTF1Bedford, PA1.0100$50,000 to $500,000
April 99:00 PM EDTF1Cambria, PA1.0100$50,000 to $500,000
April 99:18 PM EDTF1Cambria, PA2.0100$50,000 to $500,000
April 99:20 PM EDTF1Fayette, PA0.550$50,000 to $500,000
April 99:30 PM EDTF1Cambria, PA0.550$500 to $5,000
April 99:50 PM EDTF0Centre, PA0.560$5,000 to $50,000
April 910:00 PM EDTF1Bedford, PA0.550$5,000 to $50,000
April 910:30 PM EDTF1Cumberland, PA0.4203$50,000 to $500,000
April 910:30 PM EDTF0Cumberland, PA3.020$50,000 to $500,000

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.