Tornadoes · United States · Washington · 2013

EF1 tornado, Frederickson to Berkeley, Washington, September 30, 2013

From Frederickson to Berkeley, this EF1 tornado ran 1.0 miles across Pierce County on September 30, 2013, touching down at 7:20 AM PDT and reaching 75 yards wide. It killed nobody, and did $25,000 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
September 30, 2013
Touchdown
7:20 AM PDT (14:20 UTC)
Lifted
7:24 AM PDT (14:24 UTC)
On the ground
4 minutes
Path length
1.0 miles (1.6 km)
Path width
75 yards (69 m)
Deaths
0
Injuries
0
Property damage
$25,000
County
Pierce County
Touchdown point
47.085, -122.361
Lift-off point
47.089, -122.342
Record number
1309300820-01

What the Weather Service recorded

An EF1 tornado touched down near Frederickson.

EF1 tornado on the ground for 5 minutes or less. Path length about 1 mile. Width 75 yards. Max wind speed estimated at 110 mph. Key damage - tore off part of the roof of businesses at NW Door and again at Encon across the street, and on the Fredrickson Boeing Plant facility blew over several empty rail boxcars, knocked down a Rohn tower and several parking lot lamp posts, blew down over two dozen trees, and about a dozen vehicles with damage.

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
01:00 UTC10:19 UTCWind AdvisorySEW

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 12:38 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.

Quillayute State, WA (KUIL), 12:00Z

2.3 hours before the tornado, 188 km from the path. September 30, 2013.

Skew-T log-pSkew-T log-p diagram, Quillayute State, WA at 12:00Z on 2013-09-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 187 joules per kilogram, CIN -2, lifted condensation level 843 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Quillayute State, WA at 12:00Z on 2013-09-30The 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 48 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
187 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
317 J/kg
Mixed-layer LCL
843 m above ground
0-6 km bulk shear
48 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.1
0-3 km lapse rate
7.3 K/km

Open this sounding in Storm Lab

Quillayute State, WA (KUIL), 00:00Z

9.7 hours after it, 188 km from the path. October 1, 2013.

Skew-T log-pSkew-T log-p diagram, Quillayute State, WA at 00:00Z on 2013-10-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 150 joules per kilogram, CIN -4, lifted condensation level 858 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Quillayute State, WA at 00:00Z on 2013-10-01The 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 49 square meters per square second, 0 to 6 km bulk shear 40 knots.1939587897117136Sfc1 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
150 J/kg
Mixed-layer CIN
-4 J/kg
Surface CAPE
517 J/kg
Mixed-layer LCL
858 m above ground
0-6 km bulk shear
40 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2
0-3 km lapse rate
7.8 K/km

Open this sounding in Storm Lab

The radar

The Seattle radar (KATX), 124 km away, was scanning. The volume nearest the touchdown began at 14:21 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
14:20 UTCTORNADO1 S FredericksonPierce, WAEF1 TORNADO ON THE GROUND FOR 5 MINUTES OR LESS. PATH LENGTH ABOUT 1 MILE. WIDTH 75 YARDS. DAMAGE ABOUT 25 THOUSAND DOLLARS. MAX WIND SPEED ESTIMATED AT 110 MPH. KEY DAMAGE - TORE OFF PART OF THE ROOF AT NW ROOF AND AGAI
15:57 UTCHEAVY RAIN 1.265 Nnw Grand MoundThurston, WA24 HOUR RAINFALL.
17:08 UTCHEAVY RAIN 2.5IssaquahKing, WARAINFALL IN 24 HOURS. SPOTTER NEAR SQUAK MOUNTAIN.

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

This ground now

The live radar over the trackEvery 2013 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.