Alert archive / California / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 9, NWS Eureka, CA

July 30, 2025Trinity County, California

NWS Eureka, CA issued this severe thunderstorm warning at Jul 30, 2025, 6:05 PM PDT for Trinity County, California. It was in force for 40 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: Jul 30, 2025, 6:05 PM PDT (01:05 UTC)
Expired: Jul 30, 2025, 6:45 PM PDT
In force: 40 min
Issued by: NWS Eureka, CA
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Trinity County, CA

The radar

The Medford radar (KMAX), 126 km from the middle of the area, began a volume at 01:04 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
Jul 30, 6:29 PM PDT	HAIL 1	9 S Trinity Center, CA	Report of half inch to quarter sized hail near Trinity Lake.

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 00:00Z, 1.1 hours before the alert went out and 158 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: 509 J/kg
Mixed-layer CIN: -99 J/kg
Mixed-layer LCL: 2891 m above ground
0-6 km bulk shear: 20 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 60 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

693 
WUUS56 KEKA 310105
SVREKA
CAC105-310145-
/O.NEW.KEKA.SV.W.0009.250731T0105Z-250731T0145Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Eureka CA
605 PM PDT Wed Jul 30 2025

The National Weather Service in Eureka has issued a

* Severe Thunderstorm Warning for...
  East Central Trinity County in northwestern California...

* Until 645 PM PDT.

* At 605 PM PDT, a severe thunderstorm was located 9 miles north of 
  Weaverville, moving southwest at 5 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind
           damage to roofs, siding, and trees.

* Locations impacted include...
  Weaverville and Lewiston.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek shelter inside a well-built structure and stay away from 
windows. This storm is capable of producing damaging winds and large 
hail.

&&

LAT...LON 4104 12283 4096 12260 4096 12261 4094 12260
      4094 12261 4093 12261 4072 12275 4087 12310
      4099 12294 4100 12292 4099 12292 4100 12291
TIME...MOT...LOC 0104Z 45DEG 4KT 4089 12290

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JJW

1 follow-up statement

999 
WWUS56 KEKA 310135
SVSEKA

Severe Weather Statement
National Weather Service Eureka CA
635 PM PDT Wed Jul 30 2025

CAC105-310145-
/O.EXP.KEKA.SV.W.0009.000000T0000Z-250731T0145Z/
Trinity CA-
635 PM PDT Wed Jul 30 2025

...SEVERE THUNDERSTORM WARNING WILL EXPIRE AT 645 PM PDT FOR EAST 
CENTRAL TRINITY COUNTY...

&&

LAT...LON 4104 12283 4096 12260 4096 12261 4094 12260
      4094 12261 4093 12261 4072 12275 4087 12310
      4099 12294 4100 12292 4099 12292 4100 12291
TIME...MOT...LOC 0105Z 45DEG 4KT 4089 12290

$$

JJW

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 30, 5:03 PM PDT	Special Weather Statement	EKA	Trinity	27 min
Jul 30, 5:10 PM PDT	Severe Thunderstorm Warning	EKA	Trinity	50 min
Jul 30, 5:17 PM PDT	Areal Flood Advisory	EKA	Trinity	20 min
Jul 30, 5:18 PM PDT	Special Weather Statement	EKA		27 min
Jul 30, 5:23 PM PDT	Special Weather Statement	EKA	Trinity	37 min
Jul 30, 5:27 PM PDT	Special Weather Statement	EKA	Trinity	33 min
Jul 30, 5:37 PM PDT	Flash Flood Warning	EKA	Trinity	3 hr
Jul 30, 5:47 PM PDT	Special Weather Statement	EKA	Trinity	28 min
Jul 30, 6:23 PM PDT	Areal Flood Advisory	EKA	Trinity	3 hr
Jul 31, 4:01 PM PDT	Special Weather Statement	EKA	Trinity	29 min
Jul 31, 4:08 PM PDT	Special Weather Statement	EKA	Trinity	37 min
Jul 31, 4:25 PM PDT	Special Weather Statement	EKA	Trinity	35 min
Jul 31, 4:30 PM PDT	Special Weather Statement	EKA	Siskiyou	30 min
Jul 31, 4:41 PM PDT	Special Weather Statement	EKA	Trinity	34 min
Jul 31, 4:43 PM PDT	Special Weather Statement	EKA	Trinity	32 min

Nearby

Severe Thunderstorm Warnings in California, 2025 Every severe thunderstorm warning in 2025

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.