Tornadoes · United States · California · 2017

EF0 tornado, Lincoln, California, January 9, 2017

This EF0 tornado ran 0.2 miles across Placer County on January 9, 2017, touching down at 2:00 PM PST and reaching 20 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.

  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
January 9, 2017
Touchdown
2:00 PM PST (22:00 UTC)
Lifted
2:02 PM PST (22:02 UTC)
On the ground
2 minutes
Path length
0.2 miles (0.3 km)
Path width
20 yards (18 m)
Deaths
0
Injuries
0
County
Placer County
Touchdown point
38.849, -121.327
Lift-off point
38.850, -121.324
Record number
1701091600-01

What the Weather Service recorded

Two strong storms brought a range of significant weather impacts to northern interior California. The first storm was very wet and warm, the second not quite as wet but cooler with lower snow levels. Both storms brought strong, damaging winds. The heavy rain brought widespread flooding of small streams and rivers, with some flooding of main stem rivers, mountain snow many feet deep, and numerous trees down on roads, vehicles, and homes. Many roads, including major highways such as Interstate 80, were shut down due to mudslides, heavy snow, flooding, washouts or avalanche suppression. EF0 tornadoes were reported at Lincoln and Natomas. Other significant impacts include numerous accidents due to slippery roads, evacuations and rescues due to flooding.

A brief tornado touchdown was photographed out in a grassy field in Lincoln, near Thunder Valley Casino, causing no 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
09:29 UTC21:15 UTCFlood WarningREV

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.

Oakland, CA (KOAK), 12:00Z

10.0 hours before the tornado, 146 km from the path. January 9, 2017.

Skew-T log-pSkew-T log-p diagram, Oakland, CA at 12:00Z on 2017-01-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 29 joules per kilogram, CIN -15, lifted condensation level 728 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 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, Oakland, CA at 12:00Z on 2017-01-09The 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 -73 square meters per square second, 0 to 6 km bulk shear 71 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
29 J/kg
Mixed-layer CIN
-15 J/kg
Surface CAPE
240 J/kg
Mixed-layer LCL
728 m above ground
0-6 km bulk shear
71 kt
0-1 km bulk shear
27 kt
0-1 km storm-relative helicity
-73 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.1
0-3 km lapse rate
6.7 K/km

Open this sounding in Storm Lab

Oakland, CA (KOAK), 00:00Z

2.0 hours after it, 146 km from the path. January 10, 2017.

Skew-T log-pSkew-T log-p diagram, Oakland, CA at 00:00Z on 2017-01-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 53 joules per kilogram, CIN -5, lifted condensation level 969 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 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, Oakland, CA at 00:00Z on 2017-01-10The 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 103 square meters per square second, 0 to 6 km bulk shear 82 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
53 J/kg
Mixed-layer CIN
-5 J/kg
Surface CAPE
467 J/kg
Mixed-layer LCL
969 m above ground
0-6 km bulk shear
82 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
103 m²/s²
0-3 km storm-relative helicity
303 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5
0-3 km lapse rate
6.7 K/km

Open this sounding in Storm Lab

The radar

The Sacramento radar (KDAX), 49 km away, was scanning. The volume nearest the touchdown began at 21:59 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
21:00 UTCHEAVY RAIN 3.552 S AntelopeSacramento, CATHERE WERE 11.25 INCHES MEASURED AT ARCADE CREEK. THE DURATION OF THE HEAVY RAIN EVENT WAS 72 HOURS.
22:00 UTCFUNNEL CLOUD5 Ssw SheridanPlacer, CAA FUNNEL CLOUD WAS PHOTOGRAPHED FROM LINCOLN, LOOKING TOWARD RIO LINDA. NO TOUCHDOWN OR DAMAGE REPORTED.

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

This ground now

The live radar over the trackEvery 2017 tornado in CaliforniaEvery tornado in California since 1950Warnings in force in California 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.