Alert archive / California / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 4, NWS Eureka, CA

August 5, 2012Trinity County, California

NWS Eureka, CA issued this severe thunderstorm warning at Aug 5, 2012, 4:18 PM PDT for Trinity County, California. It was in force for 27 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, 4:18 PM PDT (23:18 UTC)
Expired: Aug 5, 2012, 4:45 PM PDT
In force: 27 min
Issued by: NWS Eureka, CA
Area: Storm-based polygon

County Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 79 km from the middle of the area, began a volume at 23:20 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

Time	Report	Where	Remark
Aug 5, 4:20 PM PDT	HAIL 0.25	Burnt Ranch, CA	PUBLIC PERSON LIVING IN BURNT RANCH SAID THAT THERE IS NUMEROUS THUNDERSTORMS. COULD SEE PLENTY OF HAIL ON IRONSIDE MOUNTAIN...BUT NOT ABLE TO VERIFY SIZE.

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, 11.3 hours before the alert went out and 184 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: 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.

876 
WUUS56 KEKA 052318
SVREKA
CAC105-052345-
/O.NEW.KEKA.SV.W.0004.120805T2318Z-120805T2345Z/

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

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  TRINITY COUNTY IN NORTHWEST CALIFORNIA...

* UNTIL 445 PM PDT

* AT 416 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 7 MILES
  SOUTHEAST OF BURNT RANCH...OR 18 MILES SOUTHEAST OF WILLOW CREEK...
  AND MOVING NORTH AT 25 MPH.

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

LAT...LON 4083 12353 4088 12335 4071 12337 4070 12342
TIME...MOT...LOC 2318Z 165DEG 22KT 4075 12342

$$

BFG

1 follow-up statement

252 
WWUS56 KEKA 052327
SVSEKA

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE
427 PM PDT SUN AUG 5 2012

CAC105-052345-
/O.CON.KEKA.SV.W.0004.000000T0000Z-120805T2345Z/
TRINITY CA-
427 PM PDT SUN AUG 5 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM PDT
FOR TRINITY COUNTY...

AT 424 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 OVER TRINITY COUNTY...OR 15 MILES SOUTHEAST OF WILLOW
CREEK...MOVING NORTH AT 10 MPH.

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

LAT...LON 4075 12337 4073 12342 4084 12348 4086 12343
      4088 12336 4085 12335
TIME...MOT...LOC 2327Z 165DEG 22KT 4080 12344

$$

BFG

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 5, 3:22 PM PDT	Special Weather Statement	EKA	Trinity	38 min
Aug 5, 3:26 PM PDT	Severe Thunderstorm Warning	EKA	Humboldt, Trinity	34 min
Aug 5, 3:58 PM PDT	Severe Thunderstorm Warning	EKA	Trinity	16 min
Aug 5, 4:31 PM PDT	Severe Thunderstorm Warning	EKA	Trinity	29 min

Nearby

Severe Thunderstorm Warnings in California, 2012 Every 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.