Alert archive / California / Beach Hazards Statements in 2020
Beach Hazards Statement 12, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this beach hazards statement at Dec 1, 2020, 11:28 AM PST for 6 counties in California. It took effect at Dec 2, 2020, 10:00 AM PST. It was in force for 59 hr.
The area
The counties it named.
The facts
- Issued
- Dec 1, 2020, 11:28 AM PST (19:28 UTC)
- In effect from
- Dec 2, 2020, 10:00 AM PST
- Expired
- Dec 4, 2020, 9:00 PM PST
- In force
- 59 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 nearest sounding before it
Oakland, CA (KOAK), launched 12:00Z, 7.5 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1544 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- -15 m²/s²
- 0-3 km storm-relative helicity
- -3 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
536 WHUS46 KMTR 011928 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 1128 AM PST Tue Dec 1 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... .A very long period WNW swell will impact the Sonoma to Big Sur coast through the day on Wednesday and persist into Thursday. Initial forerunner waves of 24 to 27 seconds will begin to arrive along the Sonoma coast overnight Tuesday night into early Wednesday morning before spreading southward through the day. The primary timeframe of concern from this event will be midday Wednesday into Thursday morning as the wave heights rise to 3 to 7 feet at a periodicity of 19 to 24 seconds. A high to extreme risk of sneaker waves will exist during this timeframe. The largest energetic sneaker waves will arrive irregularly every few minutes to as infrequently as once every 30 minutes during otherwise deceptively calmer seas and consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These type of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. Finally, moderate to locally large breaking waves of 14 to 18 feet will be possible later in the day on Thursday at WNW facing beaches as the swell period decreases and swell heights increase, thus this product will be in effect through the day Thursday. CAZ006-505-509-530-020600- /O.NEW.KMTR.BH.S.0012.201202T1800Z-201204T0000Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 1128 AM PST Tue Dec 1 2020 ...BEACH HAZARDS STATEMENT IN EFFECT FROM WEDNESDAY MORNING THROUGH THURSDAY AFTERNOON... The National Weather Service in San Francisco has issued a Beach Hazards Statement for dangerous sneaker waves and rip currents, which is in effect from Wednesday morning through Thursday afternoon. * WHAT...A very long period WNW swell with initial periods in excess of 20 seconds will bring a threat of dangerous sneaker waves to area beaches. Enhanced strength of rip currents and moderate to large breaking waves at the end of the event. * WHEN...10 AM Wednesday morning through 4 PM Thursday evening. * WHERE...Entire coast from Sonoma southward through Big Sur, excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W-WNW beaches,including but not limited to: Ocean beach, Montara state beach, Halfmoon bay state beach, Manresa state beach, Marina state beach.Coastline from sonoma county south through Monterey county. * IMPACTS...Potential sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$ DRP
12 follow-up statements
453 WHUS46 KMTR 011938 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 1138 AM PST Tue Dec 1 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... .A very long period WNW swell will impact the Sonoma to Big Sur coast through the day on Wednesday and persist into Thursday. Initial forerunner waves of 24 to 27 seconds will begin to arrive along the Sonoma coast overnight Tuesday night into early Wednesday morning before spreading southward through the day. The primary timeframe of concern from this event will be midday Wednesday into Thursday morning as the wave heights rise to 3 to 7 feet at a periodicity of 19 to 24 seconds. A high to extreme risk of sneaker waves will exist during this timeframe. The largest energetic sneaker waves will arrive irregularly every few minutes to as infrequently as once every 30 minutes during otherwise deceptively calmer seas and consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These type of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. Finally, moderate to locally large breaking waves of 14 to 18 feet will be possible later in the day on Thursday at WNW facing beaches as the swell period decreases and swell heights increase, thus this product will be in effect through the day Thursday. CAZ006-505-509-530-020600- /O.CON.KMTR.BH.S.0012.201202T1800Z-201204T0000Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 1138 AM PST Tue Dec 1 2020 ...BEACH HAZARDS STATEMENT IN EFFECT FROM 10 AM WEDNESDAY MORNING THROUGH 4 PM THURSDAY AFTERNOON... * WHAT...A very long period WNW swell with initial periods in excess of 20 seconds will bring a threat of dangerous sneaker waves to area beaches. Enhanced strength of rip currents and moderate to large breaking waves at the end of the event. * WHEN...10 AM Wednesday morning through 4 PM Thursday afternoon. * WHERE...Entire coast from Sonoma southward through Big Sur, excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W-WNW beaches,including but not limited to: Ocean beach, Montara state beach, Halfmoon Bay state beach, Manresa state beach, Marina state beach. * IMPACTS...Potential sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$
393 WHUS46 KMTR 020530 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 930 PM PST Tue Dec 1 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... .A very long period WNW swell will impact the Sonoma to Big Sur coast through the day on Wednesday and persist into Thursday. Initial forerunner waves of 24 to 27 seconds will begin to arrive along the Sonoma coast overnight tonight into early Wednesday morning before spreading southward through the day. The primary timeframe of concern from this event will be midday Wednesday into Thursday morning as the wave heights rise to 3 to 7 feet at a periodicity of 19 to 24 seconds. A high to extreme risk of sneaker waves will exist during this timeframe. The largest energetic sneaker waves will arrive irregularly every few minutes to as infrequently as once every 30 minutes during otherwise deceptively calmer seas and consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These type of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. Finally, moderate to locally large breaking waves of 14 to 18 feet will be possible later in the day on Thursday at WNW facing beaches as the swell period decreases and swell heights increase, thus this product will be in effect through the day Thursday. CAZ006-505-509-530-021800- /O.CON.KMTR.BH.S.0012.201202T1800Z-201204T0000Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 930 PM PST Tue Dec 1 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT FROM WEDNESDAY MORNING THROUGH THURSDAY AFTERNOON... * WHAT...A very long period WNW swell with initial periods in excess of 20 seconds will bring a threat of dangerous sneaker waves to area beaches. Enhanced strength of rip currents and moderate to large breaking waves at the end of the event. * WHEN...10 AM Wednesday morning through 4 PM Thursday afternoon. * WHERE...Entire coast from Sonoma southward through Big Sur, excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W-WNW beaches,including but not limited to: Ocean beach, Montara state beach, Halfmoon Bay state beach, Manresa state beach, Marina state beach. * IMPACTS...Potential sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$
572 WHUS46 KMTR 021731 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 931 AM PST Wed Dec 2 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... .A very long period WNW swell will impact the Sonoma to Big Sur coast through the day today and persist into Thursday. Initial forerunner waves of 24 to 27 seconds will begin to arrive along the Sonoma coast this morning before spreading southward through the day. The primary timeframe of concern from this event will be midday today into Thursday morning as the wave heights rise to 3 to 7 feet at a periodicity of 19 to 24 seconds. A high to extreme risk of sneaker waves will exist during this timeframe. The largest energetic sneaker waves will arrive irregularly every few minutes to as infrequently as once every 30 minutes during otherwise deceptively calmer seas and consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These type of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. Finally, moderate to locally large breaking waves of 14 to 18 feet will be possible later in the day on Thursday at WNW facing beaches as the swell period decreases and swell heights increase, thus this product will be in effect through the day Thursday. CAZ006-505-509-530-030700- /O.CON.KMTR.BH.S.0012.201202T1800Z-201204T0000Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 931 AM PST Wed Dec 2 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT THROUGH THURSDAY AFTERNOON... * WHAT...A very long period WNW swell with initial periods in excess of 20 seconds will bring a threat of dangerous sneaker waves to area beaches. Enhanced strength of rip currents. Moderate to large breaking waves at the end of the event Thursday. * WHEN...10 AM Wednesday morning through 4 PM Thursday afternoon. * WHERE...Entire coast from Sonoma southward through Big Sur, excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W-WNW beaches,including but not limited to: Ocean beach, Montara state beach, Halfmoon Bay state beach, Manresa state beach, Marina state beach. * IMPACTS...Potential sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$
480 WHUS46 KMTR 030433 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 833 PM PST Wed Dec 2 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... .A very long period WNW swell will continue to impact our coast from Sonoma southward to Big Sur tonight and Thursday. The primary timeframe of concern for this event is tonight and Thursday morning, with wave heights rising to 3 to 7 feet with periods of 19 to 24 seconds. The result is a high to extreme risk of sneaker waves. The largest energetic sneaker waves will arrive irregularly every few minutes to as infrequently as once every 30 minutes during otherwise deceptively calmer seas and consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. Finally, moderate to locally large breaking waves of 14 to 18 feet will be possible later in the day on Thursday at WNW facing beaches as the swell period decreases and swell heights increase, thus this product will be in effect through the day Thursday. CAZ006-505-509-530-031300- /O.CON.KMTR.BH.S.0012.000000T0000Z-201204T0000Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 833 PM PST Wed Dec 2 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT THROUGH THURSDAY AFTERNOON... * WHAT...A very long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves towards the end of the event Thursday afternoon. * WHEN...Continuing through 4 PM Thursday afternoon. * WHERE...Entire coast from Sonoma southward to Big Sur, excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W-WNW beaches,including but not limited to: Ocean beach, Montara state beach, Half Moon Bay state beach, Manresa state beach, and Marina state beach. * IMPACTS...Potential sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$
550 WHUS46 KMTR 031344 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 544 AM PST Thu Dec 3 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... .A very long period WNW swell will continue to impact our coast from Sonoma southward to Big Sur today. Expect moderate to locally large breaking waves of 14 to 18 feet, especially at WNW facing beaches, while swell periods of 20 to 23 seconds decrease. The result is a high to extreme risk of sneaker waves. The largest energetic sneaker waves will arrive irregularly every few minutes to as infrequently as once every 30 minutes during otherwise deceptively calmer seas and consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. A beach hazard statement remains in effect through 4 PM today. CAZ006-505-509-530-040000- /O.CON.KMTR.BH.S.0012.000000T0000Z-201204T0000Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 544 AM PST Thu Dec 3 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT UNTIL 4 PM PST THIS AFTERNOON... * WHAT...A very long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves towards the end of the event this afternoon. * WHEN...Continuing through 4 PM this afternoon. * WHERE...Entire coast from Sonoma southward to Big Sur, excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W-WNW beaches,including but not limited to: Ocean beach, Montara state beach, Half Moon Bay state beach, Manresa state beach, and Marina state beach. * IMPACTS...Potential sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$
540 WHUS46 KMTR 031708 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 908 AM PST Thu Dec 3 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... .A very long period WNW swell will continue to impact our coast from Sonoma through Monterey Counties today. Expect moderate to locally large breaking waves generally 14 to 18 feet with isolated peak locations potentially reaching 18 to 25 feet. With building height and periods in the 18+ second range, the result is an extreme risk of sneaker waves. The largest and most energetic sneaker waves will arrive irregularly, from every few minutes to as infrequently as once every 30 minutes during otherwise deceptively calmer seas. These consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. A beach hazard statement remains in effect through 4 PM today, but may be extended if conditions warrant. CAZ006-505-509-530-040000- /O.CON.KMTR.BH.S.0012.000000T0000Z-201204T0000Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 908 AM PST Thu Dec 3 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT UNTIL 4 PM PST THIS AFTERNOON... * WHAT...A very long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves towards the end of the event this afternoon. * WHEN...Continuing through at least 4 PM this afternoon. * WHERE...Entire coast from Sonoma County southward to the Big Sur coast of Monterey County. Excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W-WNW beaches,including but not limited to: Ocean beach, Montara state beach, Half Moon Bay state beach, Manresa state beach, and Marina state beach. * IMPACTS...Sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$
068 WHUS46 KMTR 032235 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 235 PM PST Thu Dec 3 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... Beach Hazard Statement has been extended into Friday afternoon. Long period swell will continue into Friday which will maintain the increased risk of sneaker waves and strong rip currents. While swell will peak overnight in the around 12-14 feet at 17-18 seconds, it will have a slow decline through much of Friday. Sneaker waves are waves that seem to come out of nowhere and can have a periodicity of minutes to tens of minutes. A deceptively calm ocean typically exist between the sets of sneaker waves. These consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. CAZ006-505-509-530-040645- /O.EXT.KMTR.BH.S.0012.000000T0000Z-201204T2300Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 235 PM PST Thu Dec 3 2020 ...BEACH HAZARDS STATEMENT NOW IN EFFECT THROUGH FRIDAY AFTERNOON... * WHAT...A very long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves towards the end of the event this afternoon. * WHEN...Through Friday afternoon. * WHERE...Entire coast from Sonoma County southward to the Big Sur coast of Monterey County. Excluding the sheltered northern portion of the Monterey Bay. The main impacts will be felt at W- WNW beaches,including but not limited to: Ocean beach, Montara state beach, Half Moon Bay state beach, Manresa state beach, and Marina state beach. * IMPACTS...Sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Beach Hazard Statement for sneaker waves means that conditions are present to support an increased danger 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. Beachcombing is not advised. && $$
317 WHUS46 KMTR 040625 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 1025 PM PST Thu Dec 3 2020 ...Very Long Period Swell will bring Dangerous Sneaker Waves... Beach Hazard Statement has been extended into Friday afternoon. Long period swell will continue into Friday which will maintain the increased risk of sneaker waves and strong rip currents. Swell will peak overnight at around 12-14 feet at 17- 18 seconds, and will slowly decline through much of Friday. Sneaker waves are waves that seem to come out of nowhere and can have a periodicity of minutes to tens of minutes. A deceptively calm ocean typically exists between the sets of sneaker waves. These consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. CAZ006-505-509-530-041100- /O.CON.KMTR.BH.S.0012.000000T0000Z-201204T2300Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 1025 PM PST Thu Dec 3 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT THROUGH FRIDAY AFTERNOON... * WHAT...A very long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves towards the end of the event this afternoon. * WHEN...Through Friday afternoon. * WHERE...San Francisco, Coastal North Bay Including Point Reyes National Seashore, San Francisco Peninsula Coast and Southern Monterey Bay and Big Sur Coast Counties. * IMPACTS...Sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... Remain out of the water to avoid hazardous swimming conditions. && $$
507 WHUS46 KMTR 041004 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 204 AM PST Fri Dec 4 2020 ...Long Period Swell will bring Dangerous Sneaker Waves... Beach Hazard Statement will continue into this afternoon. Long period swell will continue into this afternoon which will maintain the increased risk of sneaker waves and strong rip currents. Swell will peak overnight at around 12-14 feet at 17- 18 seconds, and will slowly decline through much of today. Sneaker waves are waves that seem to come out of nowhere and can have a periodicity of minutes to tens of minutes. A deceptively calm ocean typically exists between the sets of sneaker waves. These consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. CAZ006-505-509-530-041815- /O.CON.KMTR.BH.S.0012.000000T0000Z-201204T2300Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 204 AM PST Fri Dec 4 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT THROUGH THIS AFTERNOON... * WHAT...A long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves overnight into early this morning. * WHEN...Through this afternoon. * WHERE...San Francisco, Coastal North Bay Including Point Reyes National Seashore, San Francisco Peninsula Coast and Southern Monterey Bay and Big Sur Coast Counties. * IMPACTS...Sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... Remain out of the water to avoid hazardous swimming conditions. && $$
084 WHUS46 KMTR 041637 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 837 AM PST Fri Dec 4 2020 ...Long Period Swell will bring Dangerous Sneaker Waves... Beach Hazard Statement continues into this afternoon. Long period swell will continue into this afternoon which will maintain the increased risk of sneaker waves and strong rip currents. Swell will slowly subside today and Saturday. Sneaker waves are waves that seem to come out of nowhere and can have a periodicity of minutes to tens of minutes. A deceptively calm ocean typically exists between the sets of sneaker waves. These consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. CAZ006-505-509-530-042300- /O.CON.KMTR.BH.S.0012.000000T0000Z-201204T2300Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 837 AM PST Fri Dec 4 2020 ...BEACH HAZARDS STATEMENT REMAINS IN EFFECT UNTIL 3 PM PST THIS AFTERNOON... * WHAT...A long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves are possible through the afternoon. * WHEN...Through this afternoon. * WHERE...San Francisco, Coastal North Bay Including Point Reyes National Seashore, San Francisco Peninsula Coast and Southern Monterey Bay and Big Sur Coast Counties. * IMPACTS...Sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... Remain out of the water to avoid hazardous swimming conditions. && $$
253 WHUS46 KMTR 042231 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 231 PM PST Fri Dec 4 2020 ...Long Period Swell will bring Dangerous Sneaker Waves... Beach Hazard Statement continues into this evening. Long period swell is holding height and period this afternoon causing the risk of sneaker waves and strong rips to continue. The threat will now continue into the evening hours before the swell slowly subsides overnight. As of 2:30 pm Friday, buoys continue to report open ocean height of near 11 feet with a dominant period of 16-17 seconds. Sneaker waves are waves that seem to come out of nowhere and can have a periodicity of minutes to tens of minutes. A deceptively calm ocean typically exists between the sets of sneaker waves. These consequently may catch those on coastal jetties, rocks, piers, or shorelines offguard and may injure them or knock them into the cold, turbulent ocean. Beachcombing is not advised during this timeframe. In addition, strong rip currents will accompany the energetic wave train, particularly at WNW facing beaches. These types of events claim lives each year along our coast so extreme vigilance is advised if visiting the coast. CAZ006-505-509-530-050500- /O.EXT.KMTR.BH.S.0012.000000T0000Z-201205T0500Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 231 PM PST Fri Dec 4 2020 ...BEACH HAZARDS STATEMENT NOW IN EFFECT UNTIL 9 PM PST THIS EVENING... * WHAT...A long period WNW swell will continue to bring a threat of dangerous sneaker waves to area beaches, as well as strong rip currents. Moderate to large breaking waves are possible through this evening. * WHEN...Through this evening. * WHERE...San Francisco, Coastal North Bay Including Point Reyes National Seashore, San Francisco Peninsula Coast and Southern Monterey Bay and Big Sur Coast Counties. * IMPACTS...Sneaker waves will create dangerous conditions at area beaches. Steep beaches will have a higher risk of sneaker wave activity with greater wave run-up onto beaches. Occasionally larger waves will also wash over jetties and rock outcroppings that normally stay dry. PRECAUTIONARY/PREPAREDNESS ACTIONS... Remain out of the water to avoid hazardous swimming conditions. && $$
714 WHUS46 KMTR 050454 CFWMTR Coastal Hazard Message National Weather Service San Francisco CA 854 PM PST Fri Dec 4 2020 CAZ006-505-509-530-050600- /O.EXP.KMTR.BH.S.0012.000000T0000Z-201205T0500Z/ San Francisco- Coastal North Bay Including Point Reyes National Seashore- San Francisco Peninsula Coast- Southern Monterey Bay and Big Sur Coast- 854 PM PST Fri Dec 4 2020 ...BEACH HAZARDS STATEMENT WILL EXPIRE AT 9 PM PST THIS EVENING... Long period NW swell continues to subside this evening through Saturday morning. Please be advised that occasional large breaking waves are still possible through the morning hours. Exercise caution if you are on the beach and do not turn your back to the ocean. $$
The office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 1, 7:12 AM PST | Dense Fog Advisory | MTR | Alameda, Contra Costa, San Mateo, Santa Clara | 3 hr |
Nearby
Beach Hazards Statements in California, 2020Every beach hazards statement in 2020
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.