Alert archive / California / Special Weather Statements in 2017

Special Weather Statement, NWS Eureka, CA

August 6, 2017

NWS Eureka, CA issued this special weather statement at Aug 6, 2017, 6:08 PM PDT. It was in force for 22 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 6, 2017, 6:08 PM PDT (01:08 UTC)
Expired
Aug 6, 2017, 6:30 PM PDT
In force
22 min
Issued by
NWS Eureka, CA

The radar

The Medford radar (KMAX), 120 km from the middle of the area, began a volume at 01:13 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 00:00Z, 1.1 hours before the alert went out and 152 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 00:00Z on 2017-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 7 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 00:00Z on 2017-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 16 square meters per square second.1939Sfc1 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
7 J/kg
Mixed-layer CIN
-207 J/kg
Mixed-layer LCL
3615 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
16 m²/s²
0-3 km storm-relative helicity
39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

550 
WWUS86 KEKA 070108
SPSEKA

Special Weather Statement
National Weather Service Eureka CA
608 PM PDT SUN AUG 6 2017

CAZ107-070130-
Northern Trinity-
608 PM PDT SUN AUG 6 2017

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN TRINITY COUNTY...

At 606 PM PDT, a strong thunderstorm was located near Carrville and 
Trinity Center, around 5 miles east of Trinity Center. the storm is 
nearly stationary.

Winds in excess of 30 mph and nickel size hail are possible with this
storm.

Locations impacted include...
Carrville, Trinity Center and Highway 3. 

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

If you are on or near Trinity Lake, get out of the water and move 
indoors or inside a vehicle. Remember, lightning can strike out to 
10 miles from the parent thunderstorm. If you can hear thunder, you 
are close enough to be struck by lightning. Move to safe shelter 
now! Do not be caught on the water in a thunderstorm.

Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.

LAT...LON 4107 12254 4106 12252 4101 12253 4100 12254
      4100 12255 4099 12257 4099 12259 4097 12260
      4092 12261 4090 12260 4088 12267 4103 12279
      4118 12257 4109 12250
TIME...MOT...LOC 0106Z 094DEG 1KT 4099 12266 

$$

RCL

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 6, 5:28 PM PDTSpecial Weather StatementEKA32 min
Aug 6, 5:32 PM PDTSevere Thunderstorm WarningEKATrinity28 min
Aug 6, 11:36 PM PDTRed Flag WarningEKA20 hr
Aug 7, 3:43 PM PDTSpecial Weather StatementEKATrinity32 min
Aug 7, 3:50 PM PDTSpecial Weather StatementEKATrinity25 min
Aug 7, 3:57 PM PDTSpecial Weather StatementEKA33 min
Aug 7, 3:59 PM PDTSpecial Weather StatementEKATrinity16 min
Aug 7, 4:07 PM PDTSpecial Weather StatementEKATrinity8 min
Aug 7, 4:28 PM PDTSpecial Weather StatementEKA32 min
Aug 7, 4:40 PM PDTSpecial Weather StatementEKATrinity35 min

Nearby

Special Weather Statements in California, 2017Every special weather statement in 2017

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.