Alert archive / California / High Surf Advisories in 2021

High Surf Advisory 7, NWS Eureka, CA

October 25, 2021Del Norte County, Humboldt County, Mendocino County, California

NWS Eureka, CA issued this high surf advisory at Oct 25, 2021, 5:29 PM PDT for Del Norte County, Humboldt County, Mendocino County, California. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Oct 25, 2021, 5:29 PM PDT (00:29 UTC)
Expired
Oct 25, 2021, 11:00 PM PDT
In force
6 hr
Issued by
NWS Eureka, CA

Counties Del Norte County, CA, Humboldt County, CA, Mendocino County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 47 km from the middle of the area, began a volume at 00:30 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, 0.5 hours before the alert went out and 210 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 2021-10-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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 2021-10-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 36 square meters per square second.19395878Sfc1 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
5 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
1414 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
36 m²/s²
0-3 km storm-relative helicity
128 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

060 
WHUS46 KEKA 260029
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
529 PM PDT Mon Oct 25 2021

CAZ101-103-104-109-260600-
/O.CAN.KEKA.SU.W.0002.000000T0000Z-211026T0600Z/
/O.NEW.KEKA.SU.Y.0007.211026T0029Z-211026T0600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
529 PM PDT Mon Oct 25 2021

...HIGH SURF ADVISORY IN EFFECT UNTIL 11 PM PDT THIS EVENING...
...HIGH SURF WARNING IS CANCELLED...

* WHAT...Large breaking waves up to 25 feet possible.

* WHERE...Coastal Del Norte, Northern Humboldt Coast, 
  Southwestern Humboldt and Mendocino Coast Counties.

* WHEN...Until 11 PM PDT this evening.. .

* IMPACTS...Dangerous surfing conditions and localized beach 
  erosion. Beachcombing is highly discouraged!.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Large breaking waves along the coast will lead to increased wave
run-up on beaches with waves topping and washing over large rocks
and jetties. These large waves can be erratic and unpredictable.
Use extra caution near the surf zone as these large waves will be
capable of sweeping people into the frigid and turbulent ocean
water. Mariners traversing the bar are urged to exercise extreme
caution or stay in port until the threat subsides. Please contact
the U.S. Coast Guard for information regarding harbor and bar
closures.

&&

$$
1 follow-up statement
597 
WHUS46 KEKA 260546
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
1046 PM PDT Mon Oct 25 2021

CAZ101-103-104-109-260700-
/O.EXP.KEKA.SU.Y.0007.000000T0000Z-211026T0600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
1046 PM PDT Mon Oct 25 2021

...HIGH SURF ADVISORY WILL EXPIRE AT 11 PM PDT THIS EVENING...

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 26, 2:28 AM PDTSmall Craft AdvisoryEKA64 hr

Nearby

High Surf Advisories in California, 2021Every high surf advisory in 2021

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.