Alert archive / California / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 2, NWS Eureka, CA

August 5, 2012Humboldt County, Trinity County, California

NWS Eureka, CA issued this severe thunderstorm warning at Aug 5, 2012, 3:26 PM PDT for Humboldt County, Trinity County, California. It was in force for 34 min. 1 report 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
Aug 5, 2012, 3:26 PM PDT (22:26 UTC)
Expired
Aug 5, 2012, 4:00 PM PDT
In force
34 min
Issued by
NWS Eureka, CA
Area
Storm-based polygon

Counties Humboldt County, CA, Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 78 km from the middle of the area, began a volume at 22:28 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
Aug 5, 4:00 PM PDTHAIL 0.51 Ne Burnt Ranch, CAOBSERVER ON IRONSIDE MOUNTAIN REPORTED HAIL COVERING THE GROUND. HAIL UP TO 1/2 INCH IN DIAMETER.

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

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 12:00Z, 10.4 hours before the alert went out and 178 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, Medford/Jackson, OR at 12:00Z on 2012-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 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, Medford/Jackson, OR at 12:00Z on 2012-08-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -51 square meters per square second.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.
Mixed-layer CAPE
3 J/kg
Mixed-layer CIN
-793 J/kg
Mixed-layer LCL
2407 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-51 m²/s²
0-3 km storm-relative helicity
96 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.

765 
WUUS56 KEKA 052226
SVREKA
CAC023-105-052300-
/O.NEW.KEKA.SV.W.0002.120805T2226Z-120805T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EUREKA CA
326 PM PDT SUN AUG 5 2012

THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EAST CENTRAL HUMBOLDT COUNTY IN NORTHWEST CALIFORNIA...
  WEST CENTRAL TRINITY COUNTY IN NORTHWEST CALIFORNIA...

* UNTIL 400 PM PDT

* AT 324 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  BURNT RANCH...OR 15 MILES SOUTHEAST OF WILLOW CREEK...AND MOVING
  NORTHWEST AT 10 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  SALYER AND DENNY

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 4092 12368 4102 12341 4074 12324 4065 12344
TIME...MOT...LOC 2226Z 152DEG 9KT 4080 12343

$$

RPA
1 follow-up statement
005 
WWUS56 KEKA 052242
SVSEKA

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE EUREKA CA
342 PM PDT SUN AUG 5 2012

CAC023-105-052300-
/O.CON.KEKA.SV.W.0002.000000T0000Z-120805T2300Z/
HUMBOLDT CA-TRINITY CA-
342 PM PDT SUN AUG 5 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 PM PDT
FOR WEST CENTRAL TRINITY AND EXTREME EAST CENTRAL HUMBOLDT
COUNTIES...

AT 337 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR BURNT RANCH...OR 12 MILES SOUTHEAST OF WILLOW CREEK...
MOVING NORTHWEST AT 10 MPH.

THE SEVERE THUNDERSTORM WILL OTHERWISE REMAIN OVER MAINLY RURAL AREAS
OF THE INDICATED COUNTIES.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

&&

LAT...LON 4095 12359 4101 12343 4077 12328 4070 12342
TIME...MOT...LOC 2242Z 152DEG 9KT 4084 12345

$$

RPA

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 3:22 PM PDTSpecial Weather StatementEKATrinity38 min
Aug 5, 3:58 PM PDTSevere Thunderstorm WarningEKATrinity16 min
Aug 5, 4:18 PM PDTSevere Thunderstorm WarningEKATrinity27 min
Aug 5, 4:31 PM PDTSevere Thunderstorm WarningEKATrinity29 min

Nearby

Severe Thunderstorm Warnings in California, 2012Every severe thunderstorm warning in 2012

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.