Alert archive / California / Beach Hazards Statements in 2018

Beach Hazards Statement 7, NWS San Francisco Bay Area, CA

December 5, 20186 counties in California

NWS San Francisco Bay Area, CA issued this beach hazards statement at Dec 5, 2018, 2:57 AM PST for 6 counties in California. It took effect at Dec 5, 2018, 12:00 PM PST. It was in force for 44 hr.

The area

The counties it named.

The facts

Issued
Dec 5, 2018, 2:57 AM PST (10:57 UTC)
In effect from
Dec 5, 2018, 12:00 PM PST
Expired
Dec 7, 2018, 8:00 AM PST
In force
44 hr
Issued by
NWS San Francisco Bay Area, CA

Counties City and County of San Francisco, CA, Marin County, CA, Monterey County, CA, San Mateo County, CA, Santa Cruz County, CA, Sonoma County, CA

The radar

The San Francisco radar (KMUX), 53 km from the middle of the area, began a volume at 10:58 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

Oakland, CA (KOAK), launched 00:00Z, 11.0 hours before the alert went out and 26 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, Oakland, CA at 00:00Z on 2018-12-05Temperature 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, Oakland, CA at 00:00Z on 2018-12-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 74 square meters per square second.1939587897117Sfc1 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
1531 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
78 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

410 
WHUS46 KMTR 051057
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
257 AM PST Wed Dec 5 2018

CAZ006-505-509-529-530-052200-
/O.NEW.KMTR.BH.S.0007.181205T2000Z-181207T1600Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
257 AM PST Wed Dec 5 2018

...BEACH HAZARDS STATEMENT IN EFFECT FROM NOON PST TODAY THROUGH
FRIDAY MORNING...

The National Weather Service in San Francisco has issued a Beach
Hazards Statement for increased risk of sneaker waves, which is 
in effect from noon PST today through Friday morning. 

* WAVES AND SURF...West to northwest swell initially 3 to 5 with
  forerunners at 20 to 22 seconds. Swell will build up to 10 feet
  on Thursday with periods of 18 to 20 seconds.

* HAZARDS...Increased risk of sneaker waves on northern and 
  central California beaches.

* TIMING...Wednesday afternoon through Friday morning.

* LOCATION...Coastline from Sonoma County south through Monterey
  county. In particular west to northwest facing beaches...
  including but not limited to...Ocean Beach...Montara State 
  Beach and Marina State Beach.

* POTENTIAL IMPACTS...Steep beaches will have a higher risk of 
  sneaker wave activity with greater wave run-up onto beaches than
  normally expected. Unsuspecting beach-goers may suddenly be 
  pulled out to sea. Never turn your back to the ocean! 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Beach Hazard Statement for sneaker waves means that conditions
are present to support a heightened risk of unsuspecting beach
goers being swept into the sea by a wave. People walking along the
beach should never turn their back to the sea. Fisherman should
avoid fishing from rocks or jetties.

&&

$$
6 follow-up statements
580 
WHUS46 KMTR 052153
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
153 PM PST Wed Dec 5 2018

CAZ006-505-509-529-530-060600-
/O.CON.KMTR.BH.S.0007.000000T0000Z-181207T1600Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
153 PM PST Wed Dec 5 2018

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

* WAVES AND SURF...West to northwest swell initially 3 to 5 with 
  forerunners at 20 to 22 seconds. Swell will build up to 10 
  feet on Thursday with periods of 18 to 20 seconds. 

* HAZARDS...Increased risk of sneaker waves on northern and 
  central California beaches. 

* TIMING...Wednesday afternoon through Friday morning.

* LOCATION...Coastline from Sonoma County south through Monterey 
  county. In particular west to northwest facing beaches... 
  including but not limited to...Ocean Beach...Montara State 
  Beach and Marina State Beach. 

* POTENTIAL IMPACTS...Steep beaches will have a higher risk of 
  sneaker wave activity with greater wave run-up onto beaches 
  than normally expected. Unsuspecting beach-goers may suddenly 
  be pulled out to sea. Never turn your back to the ocean! 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Beach Hazard Statement for sneaker waves means that conditions
are present to support a heightened risk of unsuspecting beach
goers being swept into the sea by a wave. People walking along
the beach should never turn their back to the sea. Fisherman
should avoid fishing from rocks or jetties.

&&

$$
862 
WHUS46 KMTR 060448
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
848 PM PST Wed Dec 5 2018


CAZ006-505-509-529-530-061800-
/O.CON.KMTR.BH.S.0007.000000T0000Z-181207T1600Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
848 PM PST Wed Dec 5 2018

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

* WAVES AND SURF...West to northwest swell initially 3 to 5 with
  forerunners at 18 to 20 seconds. Swell will build up to 10 feet
  on Thursday. 

* HAZARDS...Increased risk of sneaker waves on northern and 
  central California beaches. 

* TIMING...Thursday through Friday morning.

* LOCATION...Coastline from Sonoma County south through Monterey 
  county. In particular west to northwest facing beaches... 
  including but not limited to...Ocean Beach...Montara State 
  Beach and Marina State Beach. 

* POTENTIAL IMPACTS...Steep beaches will have a higher risk of 
  sneaker wave activity with greater wave run-up onto beaches 
  than normally expected. Unsuspecting beach-goers may suddenly 
  be pulled out to sea. Never turn your back to the ocean! 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Beach Hazard Statement for sneaker waves means that conditions
are present to support a heightened risk of unsuspecting beach
goers being swept into the sea by a wave. People walking along
the beach should never turn their back to the sea. Fisherman
should avoid fishing from rocks or jetties.

&&

$$
732 
WHUS46 KMTR 061103
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
303 AM PST Thu Dec 6 2018

...INCREASED RISK OF SNEAKER WAVES THROUGH FRIDAY...

CAZ006-505-509-529-530-062200-
/O.CON.KMTR.BH.S.0007.000000T0000Z-181207T1600Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
303 AM PST Thu Dec 6 2018

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

* WAVES AND SURF...West to northwest swell building to 10 feet at
  18 to 20 seconds over the open ocean. Breaking waves of 17 to 20
  feet will be possible.

* HAZARDS...Increased risk of sneaker waves on northern and 
  central California beaches. 

* TIMING...Today through Friday morning.

* LOCATION...Coastline from Sonoma County south through Monterey 
  county. In particular west to northwest facing beaches... 
  including but not limited to...Ocean Beach...Montara State 
  Beach...Asilomar State Beach and Marina State Beach. 

* POTENTIAL IMPACTS...Steep beaches will have a higher risk of 
  sneaker wave activity with greater wave run-up onto beaches 
  than normally expected. Unsuspecting beach-goers may suddenly 
  be pulled out to sea. Never turn your back to the ocean! 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Beach Hazard Statement for sneaker waves means that conditions
are present to support a heightened risk of unsuspecting beach
goers being swept into the sea by a wave. People walking along
the beach should never turn their back to the sea. Fisherman
should avoid fishing from rocks or jetties.

&&

$$
571 
WHUS46 KMTR 062132
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
132 PM PST Thu Dec 6 2018

...INCREASED RISK OF SNEAKER WAVES THROUGH FRIDAY...

CAZ006-505-509-529-530-070700-
/O.CON.KMTR.BH.S.0007.000000T0000Z-181207T1600Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
132 PM PST Thu Dec 6 2018

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

* WAVES AND SURF...West to northwest swell building to 10 feet 
  at 18 to 20 seconds over the open ocean. Breaking waves of 17 
  to 20 feet will be possible. 

* HAZARDS...Increased risk of sneaker waves on northern and 
  central California beaches. 

* TIMING...Today through Friday morning.

* LOCATION...Coastline from Sonoma County south through Monterey 
  county. In particular west to northwest facing beaches... 
  including but not limited to...Ocean Beach...Montara State 
  Beach...Asilomar State Beach and Marina State Beach. 

* POTENTIAL IMPACTS...Steep beaches will have a higher risk of 
  sneaker wave activity with greater wave run-up onto beaches 
  than normally expected. Unsuspecting beach-goers may suddenly 
  be pulled out to sea. Never turn your back to the ocean! 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Beach Hazard Statement for sneaker waves means that conditions
are present to support a heightened risk of unsuspecting beach
goers being swept into the sea by a wave. People walking along
the beach should never turn their back to the sea. Fisherman
should avoid fishing from rocks or jetties.

&&

$$
864 
WHUS46 KMTR 070658
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
1058 PM PST Thu Dec 6 2018

...INCREASED RISK OF SNEAKER WAVES THROUGH FRIDAY...

CAZ006-505-509-529-530-071600-
/O.CON.KMTR.BH.S.0007.000000T0000Z-181207T1600Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
1058 PM PST Thu Dec 6 2018

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

* WAVES AND SURF...West to northwest swell building to 10 feet 
  at 18 to 20 seconds over the open ocean. Breaking waves of 17 
  to 20 feet will be possible. 

* HAZARDS...Increased risk of sneaker waves on northern and 
  central California beaches. 

* TIMING...Tonight through Friday morning.

* LOCATION...Coastline from Sonoma County south through Monterey 
  county. In particular west to northwest facing beaches... 
  including but not limited to...Ocean Beach...Montara State 
  Beach...Asilomar State Beach and Marina State Beach. 

* POTENTIAL IMPACTS...Steep beaches will have a higher risk of 
  sneaker wave activity with greater wave run-up onto beaches 
  than normally expected. Unsuspecting beach-goers may suddenly 
  be pulled out to sea. Never turn your back to the ocean! 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Beach Hazard Statement for sneaker waves means that conditions
are present to support a heightened risk of unsuspecting beach
goers being swept into the sea by a wave. People walking along
the beach should never turn their back to the sea. Fisherman
should avoid fishing from rocks or jetties.

&&

$$
353 
WHUS46 KMTR 071553
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
753 AM PST Fri Dec 7 2018


CAZ006-505-509-529-530-071700-
/O.EXP.KMTR.BH.S.0007.000000T0000Z-181207T1600Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
753 AM PST Fri Dec 7 2018

...BEACH HAZARDS STATEMENT WILL EXPIRE AT 8 AM PST THIS MORNING...

* WAVES AND SURF...Wave heights and wave periods will gradually
  decrease through the day reducing the risk for sneaker waves.
  Beach goers should still use caution as some lingering rough
  surf will still be possible.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Beach Hazard Statement for sneaker waves means that conditions
are present to support a heightened risk of unsuspecting beach
goers being swept into the sea by a wave. People walking along
the beach should never turn their back to the sea. Fisherman
should avoid fishing from rocks or jetties.

&&


$$

Nearby

Beach Hazards Statements in California, 2018Every beach hazards statement in 2018

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.