Alert archive / California / Tornado Warnings in 2011

Tornado Warning 3, NWS Sacramento, CA

May 17, 2011Tehama County, California

NWS Sacramento, CA issued this tornado warning at May 17, 2011, 6:51 PM PDT for Tehama County, California. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 17, 2011, 6:51 PM PDT (01:51 UTC)
Expired: May 17, 2011, 7:15 PM PDT
In force: 24 min
Issued by: NWS Sacramento, CA
Area: Storm-based polygon

County Tehama County, CA

The radar

The Beale AFB radar (KBBX), 74 km from the middle of the area, began a volume at 01:52 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 00:00Z, 1.9 hours before the alert went out and 261 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 42 J/kg
Mixed-layer CIN: -7 J/kg
Mixed-layer LCL: 690 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: -29 m²/s²
0-3 km storm-relative helicity: -14 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

711 
WFUS56 KSTO 180151
TORSTO
CAC103-180215-
/O.NEW.KSTO.TO.W.0003.110518T0151Z-110518T0215Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SACRAMENTO CA
651 PM PDT TUE MAY 17 2011

THE NATIONAL WEATHER SERVICE IN SACRAMENTO HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL TEHAMA COUNTY IN NORTHERN CALIFORNIA...

* UNTIL 715 PM PDT

* AT 643 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO OVER CENTRAL
  TEHAMA COUNTY...OR 13 MILES NORTHEAST OF CORNING...MOVING NORTHEAST
  AT 15 MPH.

* THE TORNADO WILL BE NEAR...
  RURAL CENTRAL TEHAMA COUNTY AT 700 PM PDT

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY REINFORCED
BUILDING. AS A LAST RESORT...SEEK SHELTER IN A CULVERT...DITCH OR LOW
SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 4021 12192 4011 12182 3995 12199 4008 12215
TIME...MOT...LOC 0148Z 226DEG 15KT 4008 12198

$$

KS/JM

2 follow-up statements

321 
WWUS56 KSTO 180207
SVSSTO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SACRAMENTO CA
707 PM PDT TUE MAY 17 2011

CAC103-180215-
/O.CON.KSTO.TO.W.0003.000000T0000Z-110518T0215Z/
TEHAMA CA-
707 PM PDT TUE MAY 17 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 715 PM PDT FOR CENTRAL
TEHAMA COUNTY...

AT 700 PM PDT...WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A
SEVERE THUNDERSTORM WITH STRONG ROTATION AND A POSSIBLE TORNADO OVER 
CENTRAL TEHAMA COUNTY...EAST OF LOS MOLINOS. THE STORM WAS MOVING TO 
THE NORTHEAST AT 10 MPH.

THE STORM WILL MOVE OVER RURAL AREAS OF CENTRAL TEHAMA COUNTY...EAST 
AND NORTHEAST OF LOS MOLINOS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A 
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE 
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

&&

LAT...LON 4021 12192 4011 12182 3995 12199 4008 12215
TIME...MOT...LOC 0203Z 226DEG 7KT 4007 12200

$$
JHM

509 
WWUS56 KSTO 180217
SVSSTO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SACRAMENTO CA
717 PM PDT TUE MAY 17 2011

CAC103-180223-
/O.EXP.KSTO.TO.W.0003.000000T0000Z-110518T0215Z/
TEHAMA CA-
717 PM PDT TUE MAY 17 2011

...THE TORNADO WARNING FOR CENTRAL TEHAMA COUNTY WILL EXPIRE AT 715
PM PDT...

A STRONG THUNDERSTORM CONTINUES OVER CENTRAL TEHAMA COUNTY EAST OF 
LOS MOLINOS...IN A RURAL PORTION OF THE COUNTY.  HAIL UP TO ONE-HALF 
INCH...DANGEROUS LIGHTNING AND LOCALLY HEAVY RAIN ARE STILL POSSIBLE 
WITH THIS STORM.  

LAT...LON 4021 12192 4011 12182 3995 12199 4008 12215
TIME...MOT...LOC 0213Z 226DEG 7KT 4008 12198

$$
JHM

The office that day

Everything else NWS Sacramento, CA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 17, 5:08 PM PDT	Severe Thunderstorm Warning	STO	Tehama	37 min
May 17, 5:55 PM PDT	Special Weather Statement	STO	Tehama	50 min

Nearby

Tornado Warnings in California, 2011 Every tornado warning in 2011 Tornadoes in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.