Alert archive / California / Beach Hazards Statements in 2018

Beach Hazards Statement 3, NWS San Francisco Bay Area, CA

June 11, 2018Marin County, Santa Cruz County, Sonoma County, California

NWS San Francisco Bay Area, CA issued this beach hazards statement at Jun 11, 2018, 8:26 AM PDT for Marin County, Santa Cruz County, Sonoma County, California. It was in force for 13 hr.

The area

The counties it named.

The facts

Issued
Jun 11, 2018, 8:26 AM PDT (15:26 UTC)
Expired
Jun 11, 2018, 9:00 PM PDT
In force
13 hr
Issued by
NWS San Francisco Bay Area, CA

Counties Marin County, CA, Santa Cruz County, CA, Sonoma County, CA

The radar

The San Francisco radar (KMUX), 98 km from the middle of the area, began a volume at 15:24 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, 3.4 hours before the alert went out and 35 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 2018-06-11Temperature 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 2018-06-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 77 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
1304 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
77 m²/s²
0-3 km storm-relative helicity
76 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

916 
WHUS46 KMTR 111526
CFWMTR

Coastal Hazard Message
National Weather Service San Francisco Bay Area
826 AM PDT Mon Jun 11 2018

...Long period southerly swell impacts south facing beaches
today... 

.A southerly swell with heights 4 to 6 feet at 17 to 19 seconds
will impact south facing beaches through the day today. This
includes most Santa Cruz county beaches as well as beaches from
Bolinas Bay through the Marin Headlands in Marin county. These
conditions can result in hazardous beach conditions due to the
increased risk of rip currents and large sneaker waves. 

CAZ505-529-120400-
/O.NEW.KMTR.BH.S.0003.180611T1526Z-180612T0400Z/
Coastal North Bay Including Point Reyes National Seashore-
Northern Monterey Bay-
826 AM PDT Mon Jun 11 2018

...BEACH HAZARDS STATEMENT IN EFFECT THROUGH THIS EVENING...

The National Weather Service in San Francisco has issued a Beach
Hazards Statement for increased chance of sneaker waves and 
rip current risk, which is in effect through this evening.


* WAVES AND SURF...Southerly swell 4 to 6 feet with a period of 17
  to 19 seconds.  

* TIMING...Monday morning through at least Monday evening.

* LOCATION...Coastal sections of marin and santa cruz counties. In
  particular south and southwest facing beaches...including but 
  not limited to...stinson beach...santa cruz boardwalk beach and 
  twin lakes beach.

* POTENTIAL IMPACTS...Increased risk of sneaker waves and rip
  currents at these beaches. Never turn your back on 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.

A Beach Hazard Statement for rip currents means that conditions 
are present to support a heightened risk of strong rip currents. 
Rip currents are typically more frequent and stronger in the 
vicinity of jetties...inlets...and piers. Swimmers caught in a rip
current should swim parallel to the coast to escape the rip 
current before trying to swim for shore. Swimmers should always 
swim near a lifeguard.

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 11, 3:04 AM PDTGale WarningMTR21 hr
Jun 11, 2:20 PM PDTGale WatchMTR13 hr
Jun 11, 2:20 PM PDTSmall Craft AdvisoryMTR5 days

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.