Alert archive / California / Tornado Warnings in 2011

Tornado Warning 1, NWS Sacramento, CA

March 21, 2011Colusa County, Glenn County, California

NWS Sacramento, CA issued this tornado warning at Mar 21, 2011, 3:05 PM PDT for Colusa County, Glenn County, California. It was in force for 40 min. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Mar 21, 2011, 3:05 PM PDT (22:05 UTC)
Expired
Mar 21, 2011, 3:45 PM PDT
In force
40 min
Issued by
NWS Sacramento, CA
Area
Storm-based polygon

Counties Colusa County, CA, Glenn County, CA

The radar

The Beale AFB radar (KBBX), 48 km from the middle of the area, began a volume at 22:05 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.

What was reported inside it

TimeReportWhereRemark
Mar 21, 3:07 PM PDTTORNADO12 N Williams, CAPRELIMINARY REPORT OF A TORNADO NEAR MAXWELL.
Mar 21, 3:10 PM PDTHAIL 1.253 N Maxwell, CA

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Oakland, CA (KOAK), launched 12:00Z, 10.1 hours before the alert went out and 182 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-pSkew-T log-p diagram, Oakland, CA at 12:00Z on 2011-03-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 joules per kilogram.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.
HodographHodograph, Oakland, CA at 12:00Z on 2011-03-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 square meters per square second.1939Sfc1 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.
Mixed-layer CAPE
6 J/kg
Mixed-layer CIN
-59 J/kg
Mixed-layer LCL
646 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
5 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

672 
WFUS56 KSTO 212205
TORSTO
CAC011-021-212245-
/O.NEW.KSTO.TO.W.0001.110321T2205Z-110321T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE SACRAMENTO CA
305 PM PDT MON MAR 21 2011

THE NATIONAL WEATHER SERVICE IN SACRAMENTO HAS ISSUED A

* TORNADO WARNING FOR...
  NORTH CENTRAL COLUSA COUNTY IN CENTRAL CALIFORNIA...
  THIS INCLUDES THE CITY OF MAXWELL...
  SOUTH CENTRAL GLENN COUNTY IN NORTHERN CALIFORNIA...

* UNTIL 345 PM PDT

* AT 300 PM PDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO NEAR
  MAXWELL...MOVING EAST AT 15 MPH.

* THE TORNADO WILL BE BETWEEN MAXWELL AND DELEVAN BETWEEN 305 AND    
  315 PM PDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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 3948 12218 3937 12194 3920 12217 3932 12238
TIME...MOT...LOC 2204Z 261DEG 11KT 3930 12221

$$
JHM
1 follow-up statement
745 
WWUS56 KSTO 212218
SVSSTO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SACRAMENTO CA
318 PM PDT MON MAR 21 2011

CAC011-021-212245-
/O.CON.KSTO.TO.W.0001.000000T0000Z-110321T2245Z/
COLUSA CA-GLENN CA-
318 PM PDT MON MAR 21 2011

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 345 PM PDT FOR
SOUTHEASTERN GLENN AND NORTH CENTRAL COLUSA COUNTIES...

AT 315 PM PDT...A TRAINED WEATHER SPOTTER REPORTED A TORNADO NEAR  
MAXWELL...MOVING NORTHEAST AT 15 MPH TOWARDS DELEVAN AND ALONG 
INTERSTATE 5.  

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THE SAFEST PLACE TO BE DURING A TORNADO IS UNDER A WORKBENCH OR 
OTHER PIECE OF STURDY FURNITURE. 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 3930 12230 3945 12219 3941 12203 3937 12194
      3921 12216
TIME...MOT...LOC 2213Z 261DEG 11KT 3930 12217

$$
JHM

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 21, 2:27 PM PDTSpecial Weather StatementSTOColusa33 min
Mar 21, 2:59 PM PDTSevere Thunderstorm WarningSTOColusa, Glenn61 min
Mar 21, 3:04 PM PDTFlood WatchSTO65 hr
Mar 21, 3:48 PM PDTTornado WarningSTOColusa, Glenn27 min
Mar 21, 3:52 PM PDTSpecial Weather StatementSTOCalaveras38 min
Mar 21, 4:15 PM PDTSpecial Weather StatementSTOButte45 min

Nearby

Tornado Warnings in California, 2011Every tornado warning in 2011Tornadoes 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.