Alert archive / California / High Surf Advisories in 2021

High Surf Advisory 3, NWS Eureka, CA

January 6, 2021Del Norte County, Humboldt County, California

NWS Eureka, CA issued this high surf advisory at Jan 6, 2021, 3:35 AM PST for Del Norte County, Humboldt County, California. It took effect at Jan 6, 2021, 9:00 AM PST. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Jan 6, 2021, 3:35 AM PST (11:35 UTC)
In effect from
Jan 6, 2021, 9:00 AM PST
Expired
Jan 6, 2021, 6:00 PM PST
In force
9 hr
Issued by
NWS Eureka, CA

Counties Del Norte County, CA, Humboldt County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 86 km from the middle of the area, began a volume at 11:35 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, 11.6 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-pSkew-T log-p diagram, Medford/Jackson, OR at 00:00Z on 2021-01-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-01-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 170 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1181 m above ground
0-6 km bulk shear
44 kt
0-1 km storm-relative helicity
170 m²/s²
0-3 km storm-relative helicity
321 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

454 
WHUS46 KEKA 061135
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
335 AM PST Wed Jan 6 2021

CAZ101>104-061945-
/O.NEW.KEKA.SU.Y.0003.210106T1700Z-210107T0200Z/
Coastal Del Norte-Del Norte Interior-Northern Humboldt Coast-
Southwestern Humboldt-
335 AM PST Wed Jan 6 2021

...HIGH SURF ADVISORY IN EFFECT FROM 9 AM THIS MORNING TO 6 PM
PST THIS EVENING...

* WHAT...Large breaking waves 20 to 23 ft.

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

* WHEN...From 9 AM this morning to 6 PM PST 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.

&&

$$
3 follow-up statements
470 
WHUS46 KEKA 061156
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
356 AM PST Wed Jan 6 2021

CAZ102-061300-
/O.CAN.KEKA.SU.Y.0003.210106T1700Z-210107T0200Z/
Del Norte Interior-
356 AM PST Wed Jan 6 2021

...HIGH SURF ADVISORY IS CANCELLED...

The initial advisory message was issued for the Del Norte 
Interior zone in error. Please disregard. 


$$

CAZ101-103-104-062000-
/O.CON.KEKA.SU.Y.0003.210106T1700Z-210107T0200Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
356 AM PST Wed Jan 6 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT FROM 9 AM THIS MORNING TO
6 PM PST THIS EVENING...

* WHAT...Large breaking waves 20 to 23 ft.

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

* WHEN...From 9 AM this morning to 6 PM PST 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.

&&

$$
014 
WHUS46 KEKA 061945
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
1145 AM PST Wed Jan 6 2021

CAZ101-103-104-070200-
/O.CON.KEKA.SU.Y.0003.000000T0000Z-210107T0200Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
1145 AM PST Wed Jan 6 2021

...HIGH SURF ADVISORY REMAINS IN EFFECT UNTIL 6 PM PST THIS
EVENING...

* WHAT...Large breaking waves 18 to 22 feet.

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

* WHEN...Until 6 PM PST 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.

&&

$$
758 
WHUS46 KEKA 070201
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
601 PM PST Wed Jan 6 2021

CAZ101-103-104-070315-
/O.EXP.KEKA.SU.Y.0003.000000T0000Z-210107T0200Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
601 PM PST Wed Jan 6 2021

...HIGH SURF ADVISORY HAS EXPIRED...

While the surf has begun to subside, breakers may continue to 
approach 20 feet through late this evening.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 6, 9:02 AM PSTGale WatchEKA17 hr
Jan 6, 2:30 PM PSTWind AdvisoryEKADel Norte, Humboldt36 hr
Jan 6, 2:41 PM PSTWinter Weather AdvisoryEKA43 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.