Alert archive / California / Severe Thunderstorm Warnings in 2003

Severe Thunderstorm Warning 4, NWS Eureka, CA

August 4, 2003Humboldt County, Trinity County, California

NWS Eureka, CA issued this severe thunderstorm warning at Aug 4, 2003, 2:52 PM PDT for Humboldt County, Trinity County, California. It was in force for 23 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: Aug 4, 2003, 2:52 PM PDT (21:52 UTC)
Expired: Aug 4, 2003, 3:15 PM PDT
In force: 23 min
Issued by: NWS Eureka, CA
Area: Counties, with a storm outline in the text

Counties Humboldt County, CA, Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 67 km from the middle of the area, began a volume at 21:54 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 12:00Z, 9.9 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-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: 368 J/kg
Mixed-layer CIN: -191 J/kg
Mixed-layer LCL: 638 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 71 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

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

882 
WUUS56 KEKA 042152
SVREKA
CAC023-105-042215-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE
250 PM PDT MON AUG 4 2003

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  HUMBOLDT COUNTY IN NORTHWEST CALIFORNIA
  THIS INCLUDES THE CITY OF WILLOW CREEK
  TRINITY COUNTY IN NORTHWEST CALIFORNIA

* UNTIL 315 PM PDT

* AT 243 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
SEVER THUNDERSTORM 5 MILES WEST OF WILLOW CREEK.  THE STORM WAS 
MOVING NORTH AT 5 MPH AND WAS CAPABLE OF PRODUCING ONE INCH HAIL. 
CUING .

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  BERRY SUMMIT AT 315 PM PDT

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY
MAY BE WASHED OUT. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO
RISE...THEREFORE SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE.

LAT...LON 4078 12376 4078 12352 4101 12349 4100 12379

MJV

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 3, 8:37 PM PDT	Flash Flood Warning	EKA	Trinity	113 min
Aug 4, 3:34 PM PDT	Severe Thunderstorm Warning	EKA	Humboldt, Trinity	41 min
Aug 4, 4:14 PM PDT	Severe Thunderstorm Warning	EKA	Humboldt, Trinity	31 min

Nearby

Severe Thunderstorm Warnings in California, 2003 Every severe thunderstorm warning in 2003

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.