Alert archive / California / Beach Hazards Statements in 2017

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

September 18, 20176 counties in California

NWS San Francisco Bay Area, CA issued this beach hazards statement at Sep 18, 2017, 2:06 PM PDT for 6 counties in California. It took effect at Sep 19, 2017, 5:00 AM PDT. It was in force for 40 hr.

The area

The counties it named.

The facts

Issued
Sep 18, 2017, 2:06 PM PDT (21:06 UTC)
In effect from
Sep 19, 2017, 5:00 AM PDT
Expired
Sep 20, 2017, 9:00 PM PDT
In force
40 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 21:12 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, 9.1 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 12:00Z on 2017-09-18Temperature 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 2017-09-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -4 square meters per square second.193958Sfc1 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
731 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-4 m²/s²
0-3 km storm-relative helicity
-15 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

263 
WHUS46 KMTR 182106
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
206 PM PDT MON SEP 18 2017

CAZ006-505-509-529-530-191400-
/O.NEW.KMTR.BH.S.0008.170919T1200Z-170922T0300Z/
SAN FRANCISCO-
COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-NORTHERN MONTEREY BAY-
SOUTHERN MONTEREY BAY AND BIG SUR COAST-
206 PM PDT MON SEP 18 2017

...BEACH HAZARDS STATEMENT IN EFFECT FROM LATE TONIGHT THROUGH
THURSDAY EVENING...

A MODERATE TO LARGE HEIGHT, LONG PERIOD NORTHWEST SWELL WILL 
BEGIN TO ARRIVE OVERNIGHT TONIGHT. FORERUNNERS WITH PERIODS OF 16
TO 18 SECONDS ARE EXPECTED BEFORE THE MAIN WAVE ENERGY BEGINS TO
ARRIVE DURING THE DAY TOMORROW WHICH WILL INCREASE THS RISK OF RIP
CURRENTS, SNEAKER WAVES, AND LARGE SHORE BREAK AT NORTHWEST FACING
BEACHES. THE WAVE TRAIN WILL PERSIST THROUGH MID WEEK BEFORE
DISSIPATING. 

THE NATIONAL WEATHER SERVICE IN SAN FRANCISCO HAS ISSUED A BEACH
HAZARDS STATEMENT FOR RIP CURRENTS, SNEAKER WAVES, AND LARGE SHORE
BREAK, WHICH IS IN EFFECT FROM LATE TONIGHT THROUGH THURSDAY 
EVENING.


* SEAS: NORTHWEST FORERUNNERS ARRIVE INITIALLY TONIGHT WITH A
  PERIOD OF 16 TO 18 SECONDS. NORTHWEST SWELL OF 6 TO 10 FEET THEN
  POSSIBLE WITH A PERIOD OF 12 TO 16 SECONDS. SEAS WILL BEGIN
  LARGER THEN DISSIPATE THROUGH MID WEEK.

* TIMING: 5AM TUESDAY MORNING THROUGH 8PM THURSDAY EVENING.

* 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: INCREASED RISK OF RIP CURRENTS... SNEAKER
  WAVES... AND LOCALLY LARGE SHORE BREAK. BEACHGOERS MAY BE
  KNOCKED OVER... INJURED... OR PULLED OUT TO SEA INTO THE COLD
  RESTLESS OCEAN. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BEACH HAZARD STATEMENT MEANS THE POTENTIALLY DANGEROUS
CONDITIONS MAY EXIST ON SPECIFIC BEACHES. THESE HAZARDS MAY
INCLUDE LARGE SHORE BREAK...STRONG RIP CURRENTS...STRONG LONGSHORE
CURRENTS AND POSSIBLY SNEAKER WAVES. ALL OF WHICH COULD BE LIFE
THREATENING. BE SURE TO ALWAYS KEEP YOUR EYES ON THE OCEAN.

&&

$$
6 follow-up statements
483 
WHUS46 KMTR 190403
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
903 PM PDT MON SEP 18 2017

CAZ006-505-509-529-530-191400-
/O.CON.KMTR.BH.S.0008.170919T1200Z-170922T0300Z/
SAN FRANCISCO-
COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-NORTHERN MONTEREY BAY-
SOUTHERN MONTEREY BAY AND BIG SUR COAST-
903 PM PDT MON SEP 18 2017

...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM 5 AM PDT
TUESDAY THROUGH THURSDAY EVENING...

THE NATIONAL WEATHER SERVICE IN SAN FRANCISCO HAS ISSUED A BEACH
HAZARDS STATEMENT FOR RIP CURRENTS, SNEAKER WAVES, AND LARGE
SHORE BREAK, WHICH IS IN EFFECT FROM LATE TONIGHT THROUGH
THURSDAY EVENING.

* SEAS: NORTHWEST FORERUNNERS ARRIVE INITIALLY TONIGHT WITH A 
  PERIOD OF 16 TO 18 SECONDS. NORTHWEST SWELL OF 6 TO 10 FEET 
  THEN POSSIBLE WITH A PERIOD OF 12 TO 16 SECONDS. SEAS WILL 
  BEGIN LARGER THEN DISSIPATE THROUGH MID WEEK. 

* TIMING: 5AM TUESDAY MORNING THROUGH 8PM THURSDAY EVENING.

* 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: INCREASED RISK OF RIP CURRENTS... SNEAKER 
  WAVES... AND LOCALLY LARGE SHORE BREAK. BEACHGOERS MAY BE 
  KNOCKED OVER... INJURED... OR PULLED OUT TO SEA INTO THE COLD 
  RESTLESS OCEAN. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BEACH HAZARD STATEMENT MEANS THE POTENTIALLY DANGEROUS
CONDITIONS MAY EXIST ON SPECIFIC BEACHES. THESE HAZARDS MAY
INCLUDE LARGE SHORE BREAK...STRONG RIP CURRENTS...STRONG
LONGSHORE CURRENTS AND POSSIBLY SNEAKER WAVES. ALL OF WHICH COULD
BE LIFE THREATENING. BE SURE TO ALWAYS KEEP YOUR EYES ON THE
OCEAN.

&&

$$
850 
WHUS46 KMTR 191342
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
642 AM PDT TUE SEP 19 2017


CAZ006-505-509-529-530-192200-
/O.CON.KMTR.BH.S.0008.000000T0000Z-170922T0300Z/
SAN FRANCISCO-
COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-NORTHERN MONTEREY BAY-
SOUTHERN MONTEREY BAY AND BIG SUR COAST-
642 AM PDT TUE SEP 19 2017

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

* SEAS: NORTHWEST FORERUNNERS ARRIVE BY MID MORNING TODAY WITH A
  PERIOD OF 16 TO 18 SECONDS. NORTHWEST SWELL OF 6 TO 10 FEET THEN
  POSSIBLE WITH A PERIOD OF 12 TO 16 SECONDS. SEAS WILL BEGIN 
  LARGER THEN DISSIPATE THROUGH MID WEEK. 

* TIMING: 5AM TUESDAY MORNING THROUGH 8PM THURSDAY EVENING.

* 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: INCREASED RISK OF RIP CURRENTS... SNEAKER 
  WAVES... AND LOCALLY LARGE SHORE BREAK. BEACHGOERS MAY BE 
  KNOCKED OVER... INJURED... OR PULLED OUT TO SEA INTO THE COLD 
  RESTLESS OCEAN. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BEACH HAZARD STATEMENT MEANS THE POTENTIALLY DANGEROUS
CONDITIONS MAY EXIST ON SPECIFIC BEACHES. THESE HAZARDS MAY
INCLUDE LARGE SHORE BREAK...STRONG RIP CURRENTS...STRONG
LONGSHORE CURRENTS AND POSSIBLY SNEAKER WAVES. ALL OF WHICH COULD
BE LIFE THREATENING. BE SURE TO ALWAYS KEEP YOUR EYES ON THE
OCEAN.

&&

$$
520 
WHUS46 KMTR 192053
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
153 PM PDT TUE SEP 19 2017

CAZ006-505-509-529-530-201400-
/O.CON.KMTR.BH.S.0008.000000T0000Z-170922T0300Z/
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 PDT TUE SEP 19 2017

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

* SEAS: NORTHWEST FORERUNNERS WITH A PERIOD OF 16 TO 18 SECONDS
  ARE ARRIVING THROUGH TUESDAY AFTERNOON. NORTHWEST SWELL OF 6 TO
  10 FEET THEN POSSIBLE WITH A PERIOD OF 12 TO 16 SECONDS. THE 
  LARGEST WAVE TRAINS ARE EXPECTED TUESDAY NIGHT THROUGH 
  WEDNESDAY. SEAS WILL DISSIPATE INTO THURSDAY.
  

* TIMING: NOW THROUGH 8PM THURSDAY EVENING.

* 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 BEACH... AND MARINA STATE BEACH. 

* POTENTIAL IMPACTS: INCREASED RISK OF RIP CURRENTS... SNEAKER 
  WAVES... AND LOCALLY LARGE SHORE BREAK. BEACHGOERS MAY BE 
  KNOCKED OVER... INJURED... OR PULLED OUT TO SEA INTO THE COLD 
  RESTLESS OCEAN. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BEACH HAZARD STATEMENT MEANS THE POTENTIALLY DANGEROUS
CONDITIONS MAY EXIST ON SPECIFIC BEACHES. THESE HAZARDS MAY
INCLUDE LARGE SHORE BREAK...STRONG RIP CURRENTS...STRONG
LONGSHORE CURRENTS AND POSSIBLY SNEAKER WAVES. ALL OF WHICH COULD
BE LIFE THREATENING. BE SURE TO ALWAYS KEEP YOUR EYES ON THE
OCEAN.

&&

$$
544 
WHUS46 KMTR 201358
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
658 AM PDT WED SEP 20 2017


CAZ006-505-509-529-530-202200-
/O.CON.KMTR.BH.S.0008.000000T0000Z-170922T0300Z/
SAN FRANCISCO-
COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-NORTHERN MONTEREY BAY-
SOUTHERN MONTEREY BAY AND BIG SUR COAST-
658 AM PDT WED SEP 20 2017

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

* SEAS: NORTHWEST SWELL WITH A PERIOD OF 13 TO 15 SECONDS WILL
  CONTINUE THROUGH THIS AFTERNOON. SWELL OF 6 TO 10 FEET THEN
  POSSIBLE WITH A PERIOD OF 12 TO 14 SECONDS. SEAS ARE EXPECTED 
  TO DISSIPATE THURSDAY EVENING. 

* TIMING: NOW THROUGH 8PM THURSDAY EVENING.

* 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 BEACH... AND MARINA STATE BEACH. 

* POTENTIAL IMPACTS: INCREASED RISK OF RIP CURRENTS... SNEAKER 
  WAVES... AND LOCALLY LARGE SHORE BREAK. BEACHGOERS MAY BE 
  KNOCKED OVER... INJURED... OR PULLED OUT TO SEA INTO THE COLD 
  RESTLESS OCEAN. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BEACH HAZARD STATEMENT MEANS THE POTENTIALLY DANGEROUS
CONDITIONS MAY EXIST ON SPECIFIC BEACHES. THESE HAZARDS MAY
INCLUDE LARGE SHORE BREAK...STRONG RIP CURRENTS...STRONG
LONGSHORE CURRENTS AND POSSIBLY SNEAKER WAVES. ALL OF WHICH COULD
BE LIFE THREATENING. BE SURE TO ALWAYS KEEP YOUR EYES ON THE
OCEAN.

&&

$$
929 
WHUS46 KMTR 202021
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
121 PM PDT WED SEP 20 2017

CAZ006-505-509-529-530-210400-
/O.EXT.KMTR.BH.S.0008.000000T0000Z-170921T0400Z/
SAN FRANCISCO-
COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-NORTHERN MONTEREY BAY-
SOUTHERN MONTEREY BAY AND BIG SUR COAST-
121 PM PDT WED SEP 20 2017

...BEACH HAZARDS STATEMENT WILL NOW EXPIRE AT UNTIL 9 PM PDT THIS
EVENING...

* SEAS: NORTHWEST SWELL OF 6 TO 10 FT WITH A PERIOD OF 12 TO 14
  SECONDS THIS AFTERNOON...DECREASING TO 4 TO 8 FT WITH A PERIOD
  OF 10 TO 12 SECONDS THIS EVENING.

* TIMING: THROUGH 9 PM PDT WEDNESDAY EVENING.

* 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 BEACH...AND MARINA STATE BEACH. 

* POTENTIAL IMPACTS: INCREASED RISK OF RIP CURRENTS...SNEAKER
  WAVES...AND LOCALLY LARGE SHORE BREAK. BEACHGOERS MAY BE KNOCKED
  OVER...INJURED...OR PULLED OUT TO SEA INTO THE COLD RESTLESS 
  OCEAN. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A BEACH HAZARD STATEMENT MEANS THE POTENTIALLY DANGEROUS
CONDITIONS MAY EXIST ON SPECIFIC BEACHES. THESE HAZARDS MAY
INCLUDE LARGE SHORE BREAK...STRONG RIP CURRENTS...STRONG
LONGSHORE CURRENTS AND POSSIBLY SNEAKER WAVES. ALL OF WHICH COULD
BE LIFE THREATENING. BE SURE TO ALWAYS KEEP YOUR EYES ON THE
OCEAN.

&&

$$
618 
WHUS46 KMTR 210404
CFWMTR

COASTAL HAZARD MESSAGE
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
904 PM PDT WED SEP 20 2017

CAZ006-505-509-529-530-210515-
/O.EXP.KMTR.BH.S.0008.000000T0000Z-170921T0400Z/
SAN FRANCISCO-
COASTAL NORTH BAY INCLUDING POINT REYES NATIONAL SEASHORE-
SAN FRANCISCO PENINSULA COAST-NORTHERN MONTEREY BAY-
SOUTHERN MONTEREY BAY AND BIG SUR COAST-
904 PM PDT WED SEP 20 2017

...BEACH HAZARDS STATEMENT HAS EXPIRED...

THE NATIONAL WEATHER SERVICE IN SAN FRANCISCO HAS ALLOWED THE 
BEACH HAZARDS STATEMENT TO EXPIRE. 

CONDITIONS HAVE IMPROVED THEREFORE THE BEACH HAZARDS STATEMENT WAS
ALLOWED TO EXPIRE.


$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 17, 9:12 PM PDTSmall Craft AdvisoryMTR108 min
Sep 17, 9:12 PM PDTSmall Craft AdvisoryMTR3 days
Sep 18, 2:26 AM PDTSmall Craft AdvisoryMTR49 hr

Nearby

Beach Hazards Statements in California, 2017Every beach hazards statement in 2017

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.