Tornadoes · United States · Oregon · 1997

F0 tornado, Ontario, Oregon, June 17, 1997

This F0 tornado ran 0.2 miles across Malheur County on June 17, 1997, touching down at 4:55 PM MDT and reaching 50 yards wide. It killed nobody.

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 mphthis tornado

    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 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. 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
F0
Date
June 17, 1997
Touchdown
4:55 PM MDT (22:55 UTC)
Path length
0.2 miles (0.3 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Malheur County
Touchdown point
44.150, -116.970
Lift-off point
44.150, -116.970
Record number
346

What the Weather Service recorded

During the evening of June 17, a severe thunderstorm developed over southeastern Oregon. This thunderstorm produced numerous downbursts of wind speeds from 70 to near 100 mph, and one confirmed tornado as it moved northeast and crossed into Idaho around 5:10 pm MDT. Downburst winds destroyed a seed company building. An estimated 8,700 acres of crops were damaged by the winds and hail. Total damage estimates reached 3 million dollars in Malheur County. An F-0 tornado touched down north of Ontario. The twister blew a pick-up truck off the road before dissipating as the parent thunderstorm moved across the Snake River into Idaho.

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

The warnings

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

Issued (UTC)ExpiredProductOffice
22:21 UTC23:30 UTCSevere Thunderstorm WarningBOI

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 General Thunderstorms Risk. The outlook in force was issued at 06:14 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.

Boise Airport, ID (KBOI), 12:00Z

10.9 hours before the tornado, 89 km from the path. June 17, 1997.

Skew-T log-pSkew-T log-p diagram, Boise Airport, ID at 12:00Z on 1997-06-17Temperature 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 -64206, lifted condensation level 2029 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Boise Airport, ID at 12:00Z on 1997-06-17The 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 3 square meters per square second, 0 to 6 km bulk shear 27 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
-64206 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
2029 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
44 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.0 K/km

Open this sounding in Storm Lab

Boise Airport, ID (KBOI), 00:00Z

1.1 hours after it, 89 km from the path. June 18, 1997.

Skew-T log-pSkew-T log-p diagram, Boise Airport, ID at 00:00Z on 1997-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 633 joules per kilogram, CIN -57, lifted condensation level 2479 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, Boise Airport, ID at 00:00Z on 1997-06-18The 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 96 square meters per square second, 0 to 6 km bulk shear 58 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
633 J/kg
Mixed-layer CIN
-57 J/kg
Surface CAPE
2079 J/kg
Mixed-layer LCL
2479 m above ground
0-6 km bulk shear
58 kt
0-1 km bulk shear
12 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.0
Supercell composite
7.2
0-3 km lapse rate
9.6 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1997 tornado in OregonEvery tornado in Oregon since 1950Warnings in force in Oregon nowThe forecast where you are

The other tornadoes of June 17, 1997

8 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 1712:45 PM CDTF0Stoddard, MO0.230
June 175:45 PM EDTF0Broward, FL0.123
June 175:20 PM CDTF1Christian, KY1.350$100,000
June 175:45 PM CDTF1Nueces, TX0.2301$80,000
June 176:28 PM CDTF1Vanderburgh, IN2.0100$500,000
June 177:13 PM CDTF1Montgomery, TN to KY1.7302$330,000
June 177:30 PM CDTF0Butler, MO0.530
June 178:25 PM CDTF0Butler, KY0.550

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.