Alert archive / California / Beach Hazards Statements in 2018

Beach Hazards Statement 8, NWS San Francisco Bay Area, CA

December 29, 20186 counties in California

NWS San Francisco Bay Area, CA issued this beach hazards statement at Dec 29, 2018, 3:05 AM PST for 6 counties in California. It took effect at Dec 29, 2018, 6:00 AM PST. It was in force for 12 hr.

The area

The counties it named.

The facts

Issued
Dec 29, 2018, 3:05 AM PST (11:05 UTC)
In effect from
Dec 29, 2018, 6:00 AM PST
Expired
Dec 29, 2018, 6:00 PM PST
In force
12 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 11:09 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, 11.1 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 2018-12-29Temperature 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 2018-12-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 square meters per square second.1939587897Sfc1 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
2784 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

538 
WHUS46 KMTR 291105
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
305 AM PST Sat Dec 29 2018

...INCREASED RISK OF SNEAKER WAVES SATURDAY...

CAZ006-505-509-529-530-300200-
/O.NEW.KMTR.BH.S.0008.181229T1400Z-181230T0200Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
305 AM PST Sat Dec 29 2018

...BEACH HAZARDS STATEMENT IN EFFECT FROM 6 AM PST THIS MORNING
THROUGH THIS AFTERNOON...

The National Weather Service in San Francisco has issued a Beach
Hazards Statement, which is in effect from 6 AM PST this morning 
through this afternoon. 

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

* TIMING...Saturday.

* 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.

&&

$$
1 follow-up statement
859 
WHUS46 KMTR 300202
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
602 PM PST Sat Dec 29 2018

CAZ006-505-509-529-530-300315-
/O.EXP.KMTR.BH.S.0008.000000T0000Z-181230T0200Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
602 PM PST Sat Dec 29 2018

...BEACH HAZARDS STATEMENT HAS EXPIRED...

$$

The office that day

Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 29, 1:15 PM PSTHigh Wind WatchMTRSan Mateo, Santa Clara, Santa Cruz13 hr
Dec 29, 2:21 PM PSTGale WatchMTR7 hr

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.