Tornadoes · United States · California · 2008
EF0 tornado, Alessandro, California, May 22, 2008
This EF0 tornado ran 0.4 miles across Riverside County on May 22, 2008, touching down at 5:40 PM PDT and reaching 10 yards wide. It killed nobody.
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.
EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- May 22, 2008
- Touchdown
- 5:40 PM PDT (00:40 UTC)
- Lifted
- 5:45 PM PDT (00:45 UTC)
- On the ground
- 5 minutes
- Path length
- 0.4 miles (0.6 km)
- Path width
- 10 yards (9 m)
- Deaths
- 0
- Injuries
- 0
- County
- Riverside County
- Touchdown point
- 33.803, -117.342
- Lift-off point
- 33.801, -117.348
- Record number
- 0805221840-01
What the Weather Service recorded
A thunderstorm developed near Redlands around 3:30 PM and quickly became severe as it moved south-southwest toward Moreno Valley along the Elsinore Convergence Zone. This storm produced large swaths of hail, flash flooding, and at least four tornadoes.
A trained weather spotter from the Lake Elsinore area captured video of a tornado between 5:40 ��� 5:45 PM. This tornado occurred in an unpopulated area near the Gavilan Hills between Woodcrest and Lake Elsinore, however the exact path is unknown. This was the fourth and final tornado produced by the storm. No reports of damage were received and this tornado was rated EF-0.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
24 minutes of warning. NWS SGX issued a tornado warning for this county at 00:16 UTC, 24 minutes before the tornado touched down, in force until 00:45 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 19:01 UTC | 19:49 UTC | Flash Flood Warning | SGX |
| 19:05 UTC | 19:45 UTC | Severe Thunderstorm Warning | SGX |
| 19:55 UTC | 22:00 UTC | Flash Flood Warning | SGX |
| 22:46 UTC | 23:30 UTC | Severe Thunderstorm Warning | SGX |
| 22:50 UTC | 00:15 UTC | Flash Flood Warning | SGX |
| 23:29 UTC | 00:15 UTC | Severe Thunderstorm Warning | SGX |
| 23:45 UTC | 00:00 UTC | Tornado Warning | SGX |
| 23:56 UTC | 00:30 UTC | Tornado Warning | SGX |
| 00:01 UTC | 01:30 UTC | Flash Flood Warning | SGX |
| 00:16 UTC | 00:45 UTC | Tornado Warning | SGX |
| 00:34 UTC | 01:00 UTC | Tornado Warning | SGX |
| 01:18 UTC | 02:45 UTC | Flash Flood Warning | SGX |
| 18:13 UTC | 22:15 UTC | Flood Advisory | SGX |
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 19:59 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.
San Diego, CA (KNKX), 00:00Z
0.7 hours before the tornado, 112 km from the path. May 23, 2008.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -63852 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 4969 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- -33 m²/s²
- 0-3 km storm-relative helicity
- 2 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.2 K/km
San Diego, CA (KNKX), 12:00Z
11.3 hours after it, 112 km from the path. May 23, 2008.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -74196 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 761 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- -1 m²/s²
- 0-3 km storm-relative helicity
- -45 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 6.3 K/km
The surface observations
March Afb/Riverside (RIV), 14 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 22:55 UTC | 61.7 | 46.58 | 180° 13 kt | 996.6 | VCSH | |
| 23:30 UTC | 60.8 | 46.4 | 360° 7 kt | 997.3 | +FC TS | |
| 23:38 UTC | 60.8 | 46.4 | 30° 8 kt | 997.6 | -TSRA | |
| 23:44 UTC | 60.8 | 48.2 | 100° 10 kt | 14 | 997.6 | +FC TSRAGS |
| 23:50 UTC | 60.8 | 48.2 | 110° 26 kt | 31 | 997.3 | +FC TSRAGR |
| 23:55 UTC | 59 | 49 | 100° 20 kt | 31 | 997.6 | +FC -TSRA |
| 00:03 UTC | 55.4 | 50 | 110° 12 kt | 998 | -TSRA | |
| 00:14 UTC | 51.8 | 46.4 | 160° 15 kt | 20 | 998 | -TSRA |
| 00:55 UTC | 52.16 | 44.78 | 200° 6 kt | 998.3 | TS VCSH | |
| 01:04 UTC | 53.6 | 46.4 | 50° 6 kt | 998.6 | -TSRA | |
| 01:55 UTC | 51.8 | 48.2 | 4 kt | 999.3 | TSRA | |
| 02:23 UTC | 190° 9 kt | 1000 | RA |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Santa Ana Mts radar (KSOX), 27 km away, was scanning. The volume nearest the touchdown began at 00:39 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 22:55 UTC | HAIL 0.75 | Calimesa | Riverside, CA | 3/4 INCH DIAMETER HAIL. HAIL ACCUMULATED 2-3 INCHES IN DEPTH. PUBLIC REPORT. |
| 23:25 UTC | FLASH FLOOD | Moreno Valley | Riverside, CA | FLASH FLOODING FORCED THE CLOSURE OF REDLANDS BLVD BETWEEN BAY AVENUE AND ALLESANDRO BLVD. TIME WAS ESTIMATED. |
| 23:30 UTC | TORNADO | 4 Se March Afb | Riverside, CA | OBSERVERS AT KRIV IN THE MORENO VALLEY AREA REPORTED A TORNADO |
| 23:42 UTC | TORNADO | March Afb | Riverside, CA | OBSERVERS AT KRIV IN THE MORENO VALLEY AREA REPORTED A TORNADO |
| 23:45 UTC | HAIL 0.5 | Moreno Valley | Riverside, CA | |
| 23:50 UTC | HAIL 0.88 | Moreno Valley | Riverside, CA | NICKEL SIZE HAIL REPORTED JUST EAST OF MARCH FIELD. TIME ESTIMATED. |
| 00:40 UTC | FUNNEL CLOUD | Lake Elsinore | Riverside, CA | A FUNNEL CLOUD WAS REPORTED OVER INTERSTATE 15 NEAR LAKE ELSINORE. |
| 01:10 UTC | FLASH FLOOD | Ontario | San Bernardino, CA | REPORTS OF FLOODED LANES AT THE INTERSTATE 10 AND 15 TRANSITION. |
| 01:11 UTC | FLASH FLOOD | Colton | San Bernardino, CA | SEVERE FLASH FLOODING REPORTED IN COLTON WITH WATER UP TO THE HOODS OF VEHICLE. |
| 01:24 UTC | FLASH FLOOD | Riverside | Riverside, CA | WATER 2 FEET DEEP WAS REPORTED ACROSS ALL LANES OF INTERSTATE 215 JUST SOUTH OF COLUMBIA AVE. |
| 01:40 UTC | FLASH FLOOD | 3 Ne Rubidoux | Riverside, CA | HOME OWNER REPORTS HOUSE FLOODING NEAR CRESTMORE. |
| 01:45 UTC | FLASH FLOOD | Riverside | Riverside, CA | BUILDING FLOODED ON CHICAGO AVENUE NEAR THE 60 AND 215 FREEWAYS. |
| 01:48 UTC | FLASH FLOOD | 2 E Colton | San Bernardino, CA | VEHICLES STUCK IN FLOOD WATERS ON INTERSTATE 10 NEAR WATERMAN AVENUE. |
| 01:53 UTC | FLASH FLOOD | 2 Nw Lake Elsinore | Riverside, CA | VEHICLE STUCK IN FLASH FLOOD ON HOSTETTLER ROAD AT TEMESCAL CANYON ROAD. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2008 tornado in CaliforniaEvery tornado in California since 1950Warnings in force in California nowThe forecast where you are
The other tornadoes of May 22, 2008
27 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 22 | 11:26 AM MDT | EF3 | Weld, CO | 38.7 | 1,760 | 1 | 78 | $147 million |
| May 22 | 12:30 PM MDT | EF1 | Weld, CO | 0.1 | 100 | 1 | ||
| May 22 | 12:58 PM MDT | EF0 | Albany, WY | 0.0 | 50 | |||
| May 22 | 12:58 PM MDT | EF2 | Albany, WY | 25.1 | 100 | 1 | $300,000 | |
| May 22 | 3:45 PM CDT | EF0 | Gove, KS | 0.5 | 10 | |||
| May 22 | 4:07 PM CDT | EF0 | Gove, KS | 3.0 | 50 | |||
| May 22 | 5:11 PM CDT | EF1 | Sheridan, KS | 17.6 | 400 | $500,000 | ||
| May 22 | 5:25 PM CDT | EF0 | Gove, KS | 10.7 | 75 | $25,000 | ||
| May 22 | 4:29 PM MDT | EF0 | Chase, NE | 0.1 | 50 | |||
| May 22 | 5:32 PM CDT | EF0 | Lane, KS | 5.4 | 100 | |||
| May 22 | 5:48 PM CDT | EF1 | Decatur, KS | 12.5 | 300 | $1.0 million | ||
| May 22 | 5:55 PM CDT | EF2 | Sheridan, KS | 9.4 | 300 | $750,000 | ||
| May 22 | 6:08 PM CDT | EF1 | Gove, KS | 8.0 | 200 | $150,000 | ||
| May 22 | 6:18 PM CDT | EF0 | Sheridan, KS | 2.0 | 75 | |||
| May 22 | 6:20 PM CDT | EF0 | Sheridan, KS | 0.5 | 50 | |||
| May 22 | 6:26 PM CDT | EF0 | Trego, KS | 5.0 | 100 | |||
| May 22 | 4:30 PM PDT | EF0 | Riverside, CA | 0.9 | 20 | |||
| May 22 | 6:31 PM CDT | EF1 | Decatur, KS to NE | 34.0 | 400 | $1.9 million | ||
| May 22 | 6:32 PM CDT | EF0 | Gove, KS | 0.5 | 25 | |||
| May 22 | 4:42 PM PDT | EF2 | Riverside, CA | 2.8 | 75 | 1 | $350,000 | |
| May 22 | 4:50 PM PDT | EF0 | Riverside, CA | 1.0 | 20 | |||
| May 22 | 8:00 PM CDT | EF1 | Ness, KS | 3.5 | 150 | |||
| May 22 | 8:05 PM CDT | EF0 | Lane, KS | 1.4 | 100 | |||
| May 22 | 8:42 PM CDT | EF0 | Trego, KS | 6.9 | 150 | |||
| May 22 | 8:57 PM CDT | EF1 | Trego, KS | 3.0 | 300 | |||
| May 22 | 8:28 PM MDT | EF1 | Laramie, WY | 0.7 | 50 | $20,000 | ||
| May 22 | 8:32 PM MDT | EF0 | Laramie, WY | 0.3 | 30 |
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.