Tornadoes · United States · Washington · 2021

EF0 tornado, Dollar Corner to Heisson, Washington, September 27, 2021

From Dollar Corner to Heisson, this EF0 tornado ran 3.9 miles across Clark County on September 27, 2021, touching down at 7:06 PM PDT and reaching 240 yards wide. It killed nobody, and did $40,000 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 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
September 27, 2021
Touchdown
7:06 PM PDT (02:06 UTC)
Lifted
7:21 PM PDT (02:21 UTC)
On the ground
15 minutes
Path length
3.9 miles (6.3 km)
Path width
240 yards (219 m)
Deaths
0
Injuries
0
Property damage
$40,000
County
Clark County
Touchdown point
45.780, -122.598
Lift-off point
45.810, -122.523
Record number
2109272006-01

What the Weather Service recorded

On the evening of Monday September 27, 2021 showers in the area were quite active as a cool upper trough moved into the region. One storm cell produced an EF-0 tornado in Battle Ground, WA.

An EF-0 tornado with estimated winds of 85 mph (DI:28 ,DOD:3) began near the intersection of NE 72nd Avenue and State Highway 502 at 45.7804 latitude, -122.5982 longitude. The tornado tracked in a northeast direction, ending up near NE 259th St. and NE 147th Ave at 45.8105 latitude and -122.5229 longitude. The tornado path was about 240 yards wide with a track length of about 3.9 miles. The estimated start and end time of the tornado is 1806PST and 1821PST. No injuries or fatalities were reported. The majority of the damage was to trees that were uprooted or snapped. Other damage included a tree that fell on an RV, and fences damaged by toppled trees.

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
02:31 UTC03:00 UTCSevere Thunderstorm WarningPQR
03:01 UTC03:16 UTCSevere Thunderstorm WarningPQR

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 00:50 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.

Salem/Mcnary, OR (KSLE), 00:00Z

2.1 hours before the tornado, 103 km from the path. September 28, 2021.

Skew-T log-pSkew-T log-p diagram, Salem/Mcnary, OR at 00:00Z on 2021-09-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 124 joules per kilogram, CIN -2, lifted condensation level 618 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, Salem/Mcnary, OR at 00:00Z on 2021-09-28The 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 -23 square meters per square second, 0 to 6 km bulk shear 85 knots.1939587897117136156Sfc1 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
124 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
381 J/kg
Mixed-layer LCL
618 m above ground
0-6 km bulk shear
85 kt
0-1 km bulk shear
21 kt
0-1 km storm-relative helicity
-23 m²/s²
0-3 km storm-relative helicity
-22 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4
0-3 km lapse rate
6.6 K/km

Open this sounding in Storm Lab

Salem/Mcnary, OR (KSLE), 12:00Z

9.9 hours after it, 103 km from the path. September 28, 2021.

Skew-T log-pSkew-T log-p diagram, Salem/Mcnary, OR at 12:00Z on 2021-09-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 33 joules per kilogram, CIN -8, lifted condensation level 503 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, Salem/Mcnary, OR at 12:00Z on 2021-09-28The 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 194 square meters per square second, 0 to 6 km bulk shear 30 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
33 J/kg
Mixed-layer CIN
-8 J/kg
Surface CAPE
31 J/kg
Mixed-layer LCL
503 m above ground
0-6 km bulk shear
30 kt
0-1 km bulk shear
23 kt
0-1 km storm-relative helicity
194 m²/s²
0-3 km storm-relative helicity
221 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

The surface observations

Pearson Airpark Vancouver (VUO), 21 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:10 UTC180° 5 kt1011.2
00:15 UTC190° 7 kt1011.5
00:20 UTC180° 7 kt1011.5
00:25 UTC210° 8 kt1011.5
00:30 UTC210° 5 kt1011.5
00:35 UTC160° 7 kt1011.2
00:40 UTC160° 5 kt1011.2
00:45 UTC160° 5 kt1011.2
00:50 UTC200° 4 kt1011.2
00:53 UTC5955190° 7 kt1011.2
00:55 UTC190° 5 kt1011.5
01:00 UTC180° 5 kt1011.5
01:05 UTC190° 5 kt1011.2
01:10 UTC190° 5 kt1011.2
01:15 UTC190° 4 kt1011.2
01:20 UTC170° 7 kt1011.5
01:25 UTC190° 5 kt1011.5
01:30 UTC180° 5 kt1011.5
01:35 UTC180° 7 kt1011.5
01:40 UTC180° 7 kt1011.9-RA
01:45 UTC160° 2 kt1011.9-RA BR
01:50 UTC190° 4 kt1011.9-RA BR
01:53 UTC5854180° 5 kt1011.9-RA BR
01:55 UTC160° 5 kt1011.9-RA
02:00 UTC170° 5 kt1011.9
02:05 UTC180° 4 kt1012.2
02:10 UTC170° 5 kt1012.2
02:15 UTC170° 5 kt1012.2
02:20 UTC180° 4 kt1012.2
02:25 UTC180° 4 kt1012.2
02:30 UTC170° 4 kt1012.2
02:35 UTC170° 4 kt1012.2
02:40 UTC170° 5 kt1012.2
02:45 UTC170° 2 kt1012.2
02:50 UTC0° 0 kt1012.2
02:53 UTC57530° 0 kt1012.2
02:55 UTC180° 2 kt1012.2
03:00 UTC160° 2 kt1012.2
03:05 UTC160° 2 kt1012.2
03:10 UTC180° 2 kt1012.2
03:20 UTC0° 0 kt1012.2
03:25 UTC0° 0 kt1012.2
03:30 UTC0° 0 kt1012.2
03:35 UTC100° 2 kt1012.5
03:40 UTC140° 4 kt1012.5
03:45 UTC150° 4 kt1012.5
03:53 UTC5653 3 kt1012.9
03:55 UTC150° 2 kt1012.9
04:00 UTC130° 4 kt1013.2
04:05 UTC150° 5 kt1013.2

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

The radar

The Portland,OR radar (KRTX), 33 km away, was scanning. The volume nearest the touchdown began at 02:08 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
02:06 UTCTORNADO2 Nw Battle GroundClark, WACORRECTS PREVIOUS TORNADO REPORT EF-0 TORNADO ESTIMATED MAX WIND GUST: 85MPH.
02:06 UTCTORNADO2 Nw Battle GroundClark, WAESTIMATED MAX WIND GUST: 85MPH.

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

This ground now

The live radar over the trackEvery 2021 tornado in WashingtonEvery tornado in Washington since 1950Warnings in force in Washington 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.