Alert archive / California / Beach Hazards Statements in 2020

Beach Hazards Statement 9, NWS Eureka, CA

November 30, 2020Del Norte County, Humboldt County, Mendocino County, California

NWS Eureka, CA issued this beach hazards statement at Nov 30, 2020, 3:26 AM PST for Del Norte County, Humboldt County, Mendocino County, California. It took effect at Dec 2, 2020, 7:00 AM PST. It was in force for 25 hr.

The area

The counties it named.

The facts

Issued
Nov 30, 2020, 3:26 AM PST (11:26 UTC)
In effect from
Dec 2, 2020, 7:00 AM PST
Expired
Dec 3, 2020, 8:00 AM PST
In force
25 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 11:31 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, 11.4 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 2020-11-30Temperature 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 2020-11-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1596 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
74 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

887 
WHUS46 KEKA 301126
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
326 AM PST Mon Nov 30 2020

CAZ101-103-104-109-302000-
/O.NEW.KEKA.BH.S.0009.201202T1500Z-201203T0800Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
326 AM PST Mon Nov 30 2020

...BEACH HAZARDS STATEMENT IN EFFECT FROM WEDNESDAY MORNING
THROUGH WEDNESDAY EVENING...

* WHAT...A long period west-northwesterly swell will bring a
  threat of sneaker waves to area beaches. 

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

* WHEN...From Wednesday morning through Wednesday evening.

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches. Occasionally larger waves will also wash over jetties
  and rock outcroppings that normally stay dry. 

* ADDITIONAL DETAILS...As the waves build on Thursday, the sneaker
  wave threat will diminish. However, some set behavior will
  remain, with occasionally larger breaking waves and greater wave
  run-up. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Caution should be used when in or near the ocean. Stay a safe
distance from the water along beaches, rock, jetties, piers, and
other waterside infrastructure. Remain out of the water to avoid
dangerous swimming conditions. Never turn your back on the ocean.
Steep beaches will have the highest risk of sneaker wave activity. 

&&

$$
10 follow-up statements
740 
WHUS46 KEKA 301951
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
1151 AM PST Mon Nov 30 2020

CAZ101-103-104-109-011100-
/O.CON.KEKA.BH.S.0009.201202T1500Z-201203T0800Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
1151 AM PST Mon Nov 30 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM WEDNESDAY
MORNING THROUGH WEDNESDAY EVENING...

* WHAT...A long period west-northwesterly swell will bring a
  threat of sneaker waves to area beaches. 

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

* WHEN...From Wednesday morning through Wednesday evening.

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches. Occasionally larger waves will also wash over jetties
  and rock outcroppings that normally stay dry. 

* ADDITIONAL DETAILS...The sneaker wave threat will diminish by
  Thursday. However, caution should still be exercised as
  occasionally larger breaking waves are always possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain out of the water to avoid hazardous swimming conditions.

&&

$$
183 
WHUS46 KEKA 010620
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
1020 PM PST Mon Nov 30 2020

CAZ101-103-104-109-011430-
/O.CON.KEKA.BH.S.0009.201202T1500Z-201203T0800Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
1020 PM PST Mon Nov 30 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM WEDNESDAY
MORNING THROUGH WEDNESDAY EVENING...

* WHAT...A long period west-northwesterly swell will bring a
  threat of sneaker waves to area beaches. 

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

* WHEN...From Wednesday morning through Wednesday evening.

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches. Occasionally larger waves will also wash over jetties
  and rock outcroppings that normally stay dry. 

* ADDITIONAL DETAILS...The sneaker wave threat will diminish by
  Thursday. However, caution should still be exercised as
  occasionally larger breaking waves are always possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain out of the water to avoid hazardous swimming conditions.

&&

$$
426 
WHUS46 KEKA 011110
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
310 AM PST Tue Dec 1 2020

CAZ101-103-104-109-011915-
/O.CON.KEKA.BH.S.0009.201202T1500Z-201203T0800Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
310 AM PST Tue Dec 1 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM WEDNESDAY
MORNING THROUGH WEDNESDAY EVENING...

* WHAT...A long period west-northwesterly swell will bring a
  threat of sneaker waves to area beaches.

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

* WHEN...From Wednesday morning through Wednesday evening.

* IMPACTS...Potential sneaker waves may create locally hazardous 
  conditions at area beaches. Steep beaches will have a higher 
  risk of sneaker wave activity with greater wave run-up onto 
  beaches. Occasionally larger waves will also wash over jetties 
  and rock outcroppings that normally stay dry.

* ADDITIONAL DETAILS...The sneaker wave threat will diminish by 
  Thursday. However, caution should still be exercised as 
  occasionally larger breaking waves are always possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain vigilant when in the surf zone to avoid sneaker waves
catching you off guard. There may be up to 30 minutes between
large waves.

&&

$$
915 
WHUS46 KEKA 011617
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
817 AM PST Tue Dec 1 2020

CAZ101-103-104-109-020515-
/O.CON.KEKA.BH.S.0009.201202T1500Z-201203T0800Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
817 AM PST Tue Dec 1 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM WEDNESDAY
MORNING THROUGH WEDNESDAY EVENING...

* WHAT...A long-period west to northwest swell will bring a 
  threat of sneaker waves to area beaches.

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

* WHEN...From Wednesday morning through Wednesday evening.

* IMPACTS...Potential sneaker waves may create locally hazardous 
  conditions at area beaches. Steep beaches will have a higher 
  risk of sneaker wave activity with greater wave run-up onto 
  beaches. Occasionally larger waves will also wash over jetties 
  and rock outcroppings that normally stay dry.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain out of the water to avoid hazardous swimming conditions.

&&

$$
739 
WHUS46 KEKA 020422
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
822 PM PST Tue Dec 1 2020

CAZ101-103-104-109-021230-
/O.EXT.KEKA.BH.S.0009.201202T1500Z-201203T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
822 PM PST Tue Dec 1 2020

...BEACH HAZARDS STATEMENT NOW IN EFFECT FROM 7 AM PST WEDNESDAY
THROUGH THURSDAY MORNING...

* WHAT...A long-period west to northwest swell will bring a 
  threat of sneaker waves to area beaches.

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

* WHEN...From Wednesday morning through Thursday morning.

* IMPACTS...Potential sneaker waves may create locally hazardous 
  conditions at area beaches. Steep beaches will have a higher 
  risk of sneaker wave activity with greater wave run-up onto 
  beaches. Occasionally larger waves will also wash over jetties 
  and rock outcroppings that normally stay dry.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain out of the water to avoid hazardous swimming conditions.

&&

$$
388 
WHUS46 KEKA 021041
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
241 AM PST Wed Dec 2 2020

CAZ104-109-021845-
/O.EXT.KEKA.BH.S.0009.201202T1800Z-201203T1600Z/
Southwestern Humboldt-Mendocino Coast-
241 AM PST Wed Dec 2 2020

...BEACH HAZARDS STATEMENT NOW IN EFFECT FROM 10 AM PST THIS
MORNING THROUGH THURSDAY MORNING...

* WHAT...A long period west-northwesterly swell will bring a
  threat of sneaker waves to area beaches.

* WHERE...Mendocino Coast and Southwestern Humboldt Counties.

* WHEN...From 10 AM PST this morning through Thursday morning.. .

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches. 

* ADDITIONAL DETAILS...Sneaker waves occur when long period 
  swells arrive in sets at the beaches. This means there may be 
  lulls up to 30 minutes between the larger sets that run much 
  farther up the beach and can catch people off guard. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain vigilant when in the surf zone to avoid sneaker waves
catching you off guard. 

&&

$$

CAZ101-103-021845-
/O.CON.KEKA.BH.S.0009.201202T1500Z-201203T1600Z/
Coastal Del Norte-Northern Humboldt Coast-
241 AM PST Wed Dec 2 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM 7 AM PST THIS
MORNING THROUGH THURSDAY MORNING...

* WHAT...A long period west-northwesterly swell will bring a
  threat of sneaker waves to area beaches.

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

* WHEN...From 7 AM PST this morning through Thursday morning.. .

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches. 

* ADDITIONAL DETAILS...Sneaker waves occur when long period 
  swells arrive in sets at the beaches. This means there may be 
  lulls up to 30 minutes between the larger sets that run much 
  farther up the beach and can catch people off guard. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain vigilant when in the surf zone to avoid sneaker waves
catching you off guard. 

&&

$$
730 
WHUS46 KEKA 021831
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
1031 AM PST Wed Dec 2 2020

CAZ101-103-104-109-030245-
/O.CON.KEKA.BH.S.0009.000000T0000Z-201203T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
1031 AM PST Wed Dec 2 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT THROUGH THURSDAY
MORNING...

* WHAT...A long-period west to northwest swell will bring a 
  threat of sneaker waves to area beaches.

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

* WHEN...From 7 AM PST this morning through Thursday morning.. .

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain vigilant when in the surf zone to avoid sneaker waves
catching you off guard. Never turn your back on the ocean!

&&

$$
496 
WHUS46 KEKA 030231
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
631 PM PST Wed Dec 2 2020

CAZ101-103-104-109-031045-
/O.CON.KEKA.BH.S.0009.000000T0000Z-201203T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
631 PM PST Wed Dec 2 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT THROUGH THURSDAY
MORNING...

* WHAT...A long-period west to northwest swell will bring a 
  threat of sneaker waves to area beaches.

* WHERE...Coastal Del Norte County, coastal Humboldt County, and 
  coastal Mendocino County.

* WHEN...Through Thursday morning.

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain out of the water to avoid hazardous swimming conditions.

&&

$$
888 
WHUS46 KEKA 030636
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
1036 PM PST Wed Dec 2 2020

CAZ101-103-104-109-031445-
/O.CON.KEKA.BH.S.0009.000000T0000Z-201203T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
1036 PM PST Wed Dec 2 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT UNTIL 8 AM PST
THURSDAY...

* WHAT...A long-period west to northwest swell will bring a 
  threat of sneaker waves to area beaches.

* WHERE...Coastal Del Norte County, coastal Humboldt County, and 
  coastal Mendocino County.

* WHEN...Through Thursday morning.

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain out of the water to avoid hazardous swimming conditions.

&&

$$
299 
WHUS46 KEKA 030959
CFWEKA

Coastal Hazard Message
National Weather Service Eureka CA
159 AM PST Thu Dec 3 2020

CAZ101-103-104-109-031600-
/O.CON.KEKA.BH.S.0009.000000T0000Z-201203T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-
159 AM PST Thu Dec 3 2020

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT UNTIL 8 AM PST THIS
MORNING...

* WHAT...A long-period west to northwest swell will bring a 
  threat of sneaker waves to area beaches.

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

* WHEN...Until 8 AM PST this morning.. .

* IMPACTS...Potential sneaker waves may create locally hazardous
  conditions at area beaches. Steep beaches will have a higher
  risk of sneaker wave activity with greater wave run-up onto
  beaches.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Don't be fooled by an ocean that looks calm: There can be 30
minutes of small waves before a sneaker wave strikes. Avoid rocks
and jetties. Avoid steep beaches. Stay much farther back from the
water and never turn your back on the ocean.

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Nov 30, 3:05 AM PSTFrost AdvisoryEKADel Norte, Humboldt, Mendocino24 hr

Nearby

Beach Hazards Statements in California, 2020Every beach hazards statement in 2020

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.