Alert archive / California / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 8, NWS Eureka, CA

August 9, 2013Trinity County, California

NWS Eureka, CA issued this severe thunderstorm warning at Aug 9, 2013, 4:29 PM PDT for Trinity County, California. It was in force for 46 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 9, 2013, 4:29 PM PDT (23:29 UTC)
Expired: Aug 9, 2013, 5:15 PM PDT
In force: 46 min
Issued by: NWS Eureka, CA
Area: Storm-based polygon

County Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 104 km from the middle of the area, began a volume at 23:32 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, 11.5 hours before the alert went out and 156 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: -341 J/kg
Mixed-layer LCL: 1211 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -7 m²/s²
0-3 km storm-relative helicity: 18 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.

760 
WUUS56 KEKA 092329
SVREKA
CAC105-100015-
/O.NEW.KEKA.SV.W.0008.130809T2329Z-130810T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE EUREKA CA
429 PM PDT FRI AUG 9 2013

THE NATIONAL WEATHER SERVICE IN EUREKA HAS ISSUED A

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

* UNTIL 515 PM PDT

* AT 423 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP TO
  GOLF BALL SIZE.  THIS STORM WAS LOCATED NEAR DENNY...OR 15 MILES   
  EAST OF WILLOW CREEK...AND ABOUT STATIONARY.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  DENNY BY 450 PM PDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

&&

LAT...LON 4079 12341 4097 12344 4112 12327 4111 12326
      4108 12324 4109 12314 4108 12311 4106 12309
TIME...MOT...LOC 2329Z 071DEG 4KT 4095 12335

$$

CARROLL

2 follow-up statements

845 
WWUS56 KEKA 092359
SVSEKA

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE EUREKA CA
459 PM PDT FRI AUG 9 2013

CAC105-100015-
/O.CON.KEKA.SV.W.0008.000000T0000Z-130810T0015Z/
TRINITY CA-
459 PM PDT FRI AUG 9 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM PDT
FOR NORTH CENTRAL TRINITY COUNTY...

AT 453 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DAMAGING
HAIL UP TO GOLF BALL SIZE ALONG WITH WIND GUSTS OVER 40 MPH. THIS 
STORM WAS LOCATED NEAR DENNY...OR 13 MILES EAST OF WILLOW CREEK...
AND NEARLY STATIONARY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

&&

LAT...LON 4105 12329 4105 12324 4103 12321 4098 12319
      4089 12329 4085 12342 4097 12344 4106 12334
TIME...MOT...LOC 2359Z 071DEG 4KT 4094 12339

$$

CARROLL

130 
WWUS56 KEKA 100017
SVSEKA

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE EUREKA CA
517 PM PDT FRI AUG 9 2013

CAC105-100027-
/O.EXP.KEKA.SV.W.0008.000000T0000Z-130810T0015Z/
TRINITY CA-
517 PM PDT FRI AUG 9 2013

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN TRINITY COUNTY
HAS EXPIRED...

LAT...LON 4105 12329 4105 12324 4103 12321 4098 12319
      4089 12329 4085 12342 4097 12344 4106 12334
TIME...MOT...LOC 2359Z 071DEG 4KT 4094 12339

$$

CARROLL

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 8, 5:49 PM PDT	Areal Flood Advisory	EKA	Trinity	3 hr
Aug 9, 2:02 AM PDT	Red Flag Warning	EKA		21 hr
Aug 9, 2:16 PM PDT	Special Weather Statement	EKA	Trinity	29 min
Aug 9, 2:40 PM PDT	Special Weather Statement	EKA	Mendocino	35 min
Aug 9, 3:11 PM PDT	Special Weather Statement	EKA	Trinity	49 min
Aug 9, 3:23 PM PDT	Special Weather Statement	EKA	Mendocino	52 min
Aug 9, 3:32 PM PDT	Severe Thunderstorm Warning	EKA	Trinity	43 min
Aug 9, 3:46 PM PDT	Severe Thunderstorm Warning	EKA	Trinity	29 min
Aug 9, 4:09 PM PDT	Special Weather Statement	EKA		36 min
Aug 9, 4:23 PM PDT	Special Weather Statement	EKA	Trinity	37 min
Aug 9, 4:53 PM PDT	Areal Flood Advisory	EKA	Trinity	3 hr

Nearby

Severe Thunderstorm Warnings in California, 2013 Every severe thunderstorm warning in 2013

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.