Tornadoes · United States · Washington · 2009

EF1 tornado, Davenport to Little Falls, Washington, May 6, 2009

From Davenport to Little Falls, this EF1 tornado ran 3.4 miles across Lincoln County on May 6, 2009, touching down at 8:28 PM PDT and reaching 30 yards wide. It killed nobody, and did $30,000 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
May 6, 2009
Touchdown
8:28 PM PDT (03:28 UTC)
Lifted
8:35 PM PDT (03:35 UTC)
On the ground
7 minutes
Path length
3.4 miles (5.4 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
Property damage
$30,000
County
Lincoln County
Touchdown point
47.774, -118.141
Lift-off point
47.801, -118.081
Record number
0905062128-01

What the Weather Service recorded

A strong thunderstorm with rotation first spawned a funnel cloud and then a tornado, which briefly touched down just northeast of Davenport. The funnel cloud was spotted 16 miles northwest of Odessa, followed by a weak tornado eight miles north-northeast of Davenport. The EF1 tornado damaged two structures. By the time the storm reached north Spokane County, the rotation had weakened and was not as evident. However, a localized area of strong downburst winds impacted an area located five miles west of Chattaroy where a portion of a metal roof was blown off an out-building near the intersection of Monroe and Crosscut roads.

A short-lived tornado from a thunderstorm touched down and caused damage to two structures. It also uprooted and snapped numerous coniferous trees, many with trunk diameters greater than 15 inches.

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.

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 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.

Spokane, WA (KOTX), 00:00Z

3.5 hours before the tornado, 128 km from the path. May 7, 2009.

Skew-T log-pSkew-T log-p diagram, Spokane, WA at 00:00Z on 2009-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1 joules per kilogram, CIN -2, lifted condensation level 583 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, Spokane, WA at 00:00Z on 2009-05-07The 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 89 square meters per square second, 0 to 6 km bulk shear 46 knots.1939587897Sfc1 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
1 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
134 J/kg
Mixed-layer LCL
583 m above ground
0-6 km bulk shear
46 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
89 m²/s²
0-3 km storm-relative helicity
117 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.5 K/km

Open this sounding in Storm Lab

Spokane, WA (KOTX), 12:00Z

8.5 hours after it, 128 km from the path. May 7, 2009.

Skew-T log-pSkew-T log-p diagram, Spokane, WA at 12:00Z on 2009-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 18 joules per kilogram, CIN -72, lifted condensation level 934 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, Spokane, WA at 12:00Z on 2009-05-07The 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 80 square meters per square second, 0 to 6 km bulk shear 42 knots.1939587897Sfc1 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
18 J/kg
Mixed-layer CIN
-72 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
934 m above ground
0-6 km bulk shear
42 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.7 K/km

Open this sounding in Storm Lab

The radar

The Spokane radar (KOTX), 38 km away, was scanning. The volume nearest the touchdown began at 03:29 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
03:28 UTCFUNNEL CLOUD8 N DavenportLincoln, WAPUBLIC REPORTED FUNNEL CLOUD WITH STORM MOVING APPROX 8 MILES NORTH OF DAVENPORT.
04:20 UTCTSTM WND DMG5 W ChattaroySpokane, WAPORTION OF METAL ROOF BLOWN OFF OUT-BUILDING NEAR INTERSECTION OF MONROE AND CROSSCUT ROADS.
04:30 UTCHAIL 0.52 Se ChattaroySpokane, WA
04:30 UTCHEAVY RAIN 0.7Deer ParkSpokane, WASPOTTER STEVENS 8 REPORTED 0.70 INCHES OF RAIN WITHIN ONE HOUR UNDER HEAVY THUNDERSTORM. HEAVY RAINFALL RESULTED IN STANDING WATER IN THE STREEETS.

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

This ground now

The live radar over the trackEvery 2009 tornado in WashingtonEvery tornado in Washington since 1950Warnings in force in Washington nowThe forecast where you are

The other tornadoes of May 6, 2009

21 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 61:19 AM CDTEF0Arkansas, AR4.425$5,000
May 62:03 AM CDTEF1Phillips, AR0.125$40,000
May 63:34 AM CDTEF1Coahoma, MS0.125$60,000
May 64:52 AM CDTEF1Drew, AR2.1100$50,000
May 67:12 AM CDTEF1Choctaw, MS7.6500$350,000
May 67:47 AM CDTEF1Noxubee, MS5.05002$300,000
May 68:20 AM CDTEF1Pickens, AL1.0300$50,000
May 68:25 AM CDTEF1Lawrence, AL3.275$250,000
May 68:31 AM CDTEF1Pickens, AL1.3100$50,000
May 68:42 AM CDTEF0Morgan, AL0.775$50,000
May 68:48 AM CDTEF1Tuscaloosa, AL0.5100$65,000
May 68:57 AM CDTEF1Tuscaloosa, AL0.2100$100,000
May 68:59 AM CDTEF2Limestone, AL10.975$1.0 million
May 69:11 AM CDTEF0Walker, AL3.4200$850,000
May 69:20 AM CDTEF1Walker, AL1.0300$260,000
May 69:24 AM CDTEF0Walker, AL0.275$25,000
May 69:45 AM CDTEF0Blount, AL0.130$2,000
May 69:50 AM CDTEF1Jefferson, AL0.450$50,000
May 64:55 PM PDTEF1Umatilla, OR1.640$50,000
May 66:15 PM PDTEF0Wallowa, OR0.210$100,000
May 610:25 PM EDTEF0Carroll, VA1.520$10,000

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.