Alert archive / California / Beach Hazards Statements in 2018

Beach Hazards Statement 1, NWS San Francisco Bay Area, CA

January 11, 20186 counties in California

NWS San Francisco Bay Area, CA issued this beach hazards statement at Jan 11, 2018, 8:44 AM PST for 6 counties in California. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued
Jan 11, 2018, 8:44 AM PST (16:44 UTC)
Expired
Jan 11, 2018, 8:00 PM PST
In force
11 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 16:46 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 12:00Z, 4.7 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 12:00Z on 2018-01-11Temperature 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 12:00Z on 2018-01-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -24 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
623 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
-24 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

051 
WHUS46 KMTR 111644
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
844 AM PST Thu Jan 11 2018

...A long period northwest swell will move through the coastal
waters into tonight...

CAZ006-505-509-529-530-120400-
/O.NEW.KMTR.BH.S.0001.180111T1644Z-180112T0400Z/
San Francisco-
Coastal North Bay Including Point Reyes National Seashore-
San Francisco Peninsula Coast-Northern Monterey Bay-
Southern Monterey Bay and Big Sur Coast-
844 AM PST Thu Jan 11 2018

...BEACH HAZARDS STATEMENT IN EFFECT UNTIL 8 PM PST THIS
EVENING...

The National Weather Service in San Francisco has issued a Beach
Hazards Statement for large shore break, dangerous rip currents, 
and sneaker waves which is in effect until 8 PM PST this evening.

* SEAS... NORTHWEST SWELLS 8 TO 10 FEET WITH A PERIOD OF 17 TO 20
  SECONDS. 

* TIMING... THROUGH 8 PM TONIGHT. 

* 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...LARGE SURF...SNEAKER WAVES...AND DANGEROUS 
  RIP CURRENTS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BEACH HAZARD STATEMENT FOR LARGE SURF AND 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. 

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 10, 9:01 PM PSTSmall Craft AdvisoryMTR54 hr
Jan 11, 3:02 AM PSTSmall Craft Advisory for Rough BarMTR23 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.