Tornadoes · United States · California · 2021

EF0 tornado, Kirkwood, California, April 25, 2021

This EF0 tornado ran 2.0 miles across Tehama County on April 25, 2021, touching down at 5:45 PM PDT and reaching 50 yards wide. It killed nobody, and did $10,000 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
April 25, 2021
Touchdown
5:45 PM PDT (00:45 UTC)
Lifted
6:00 PM PDT (01:00 UTC)
On the ground
15 minutes
Path length
2.0 miles (3.3 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$10,000
Crop damage
$20,000
County
Tehama County
Touchdown point
39.821, -122.138
Lift-off point
39.820, -122.100
Record number
2104251845-01

What the Weather Service recorded

There was an EF-0 tornado that touched down in Tehama County on Sunday evening around 5:45 pm in the town of Capay, just north of Orland and the Glenn County border. This was video-recorded by a resident in a nearby field between Watkins Rd. and Capay Rd. No damage was observed in this 15 second touchdown.||The tornado touched down again about 2 miles to the east, on Post Ave between 4th and 5th Avenues. Minor damage was reported at 2 homes, including a damaged carport, roof tiles, sheds, and trees. There were also around 40 orchard trees damaged or uprooted.

There was an EF-0 tornado that touched down in Tehama County on Sunday evening around 5:45 pm in the town of Capay, just north of Orland and the Glenn County border. This was video-recorded by a resident in a nearby field between Watkins Rd. and Capay Rd. No damage was observed in this 15 second touchdown.||The tornado touched down again about 2 miles to the east, on Post Ave between 4th and 5th Avenues. Minor damage was reported at 2 homes, including a damaged carport, roof tiles, sheds, and trees. There were also around 40 orchard trees damaged or uprooted.

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
00:14 UTC01:00 UTCSevere Thunderstorm WarningSTO

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 19:30 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.

Oakland, CA (KOAK), 00:00Z

0.8 hours before the tornado, 233 km from the path. April 26, 2021.

Skew-T log-pSkew-T log-p diagram, Oakland, CA at 00:00Z on 2021-04-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 36 joules per kilogram, CIN -1, lifted condensation level 647 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, Oakland, CA at 00:00Z on 2021-04-26The 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 -1 square meters per square second, 0 to 6 km bulk shear 29 knots.1939587897117Sfc1 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
36 J/kg
Mixed-layer CIN
-1 J/kg
Surface CAPE
196 J/kg
Mixed-layer LCL
647 m above ground
0-6 km bulk shear
29 kt
0-1 km bulk shear
3 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

Oakland, CA (KOAK), 12:00Z

11.2 hours after it, 233 km from the path. April 26, 2021.

Skew-T log-pSkew-T log-p diagram, Oakland, CA at 12:00Z on 2021-04-26Temperature 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 -3, lifted condensation level 690 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, Oakland, CA at 12:00Z on 2021-04-26The 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 24 square meters per square second, 0 to 6 km bulk shear 35 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
1 J/kg
Mixed-layer CIN
-3 J/kg
Surface CAPE
2 J/kg
Mixed-layer LCL
690 m above ground
0-6 km bulk shear
35 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
30 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.1 K/km

Open this sounding in Storm Lab

The surface observations

Chico Municipal (CIC), 22 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:55 UTC55.446.4130° 20 kt1009.1
23:48 UTC57.244.6100° 20 kt1008.5
00:51 UTC57.244.6100° 16 kt1008.1
02:00 UTC57.246.4200° 19 kt1008.5-RA

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

The radar

The Beale AFB radar (KBBX), 55 km away, was scanning. The volume nearest the touchdown began at 00:43 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
00:44 UTCTORNADO5 Nne OrlandTehama, CAA BRIEF TORNADO TOUCHDOWN WAS OBSERVED IN A FARM FIELD IN CAPAY ON APRIL 25. NO DAMAGE HAS BEEN REPORTED. A VIDEO WITH SWIRLING DUST CONFIRMED THIS WAS A TORNADO. THE TORNADO WAS ONLY ON THE GROUND FOR ABOUT 15 SECONDS.
00:46 UTCTORNADO7 Ne OrlandTehama, CAA TORNADO BRIEFLY TOUCHED DOWN ON POST AVE. BETWEEN 4TH AND 5TH AVE. IN CAPAY ON APRIL 25. MINOR DAMAGE WAS CAUSED TO 2 HOMES, INCLUDING ROOF TILES, A CARPORT ROOF, SHEDS AND SEVERAL TREES. AROUND 40 ORCHARD TREES SUFFER

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 CaliforniaEvery tornado in California since 1950Warnings in force in California nowThe forecast where you are

The other tornadoes of April 25, 2021

1 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 257:09 AM EDTEF0Flagler, FL0.3100

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.