SAN FRANCISCO (CBS SF) -- Storm systems churning to life out in the Pacific have sent large northwest swells crashing onto San Francisco Bay Area ocean beaches from Sonoma County to Monterey, triggering a warning from the National Weather Service to beachgoers to be on the alert for deadly sneaker waves and strong rip tides.
The latest storm system arrived in the Bay Area early Saturday bringing light showers to the region, but was churning up turbulent waters in the Pacific. There were at least two other storm systems lined up out in the Pacific that will arrive next week.
"Strong storms in the Pacific continue to generate large long period northwest swells for the Bay Area and Central Coast," NWS forecasters said Saturday morning. "Coastal buoys report very long period west to northwest swell. The primary hazard will be infrequent yet dangerous sneaker waves and strong rip currents."
Forecasters said "the swell will quickly build and become large this morning with breaking waves of 20 to 25 feet expected at west to northwest facing beaches, locally up to 30 feet at favored breakpoints."
Among those favored breakpoints was Mavericks big wave surf break located off the San Mateo County coast.
The weather service issued a High Surf Advisory that was to remain in effect until Sunday morning.
"Sea surface temperatures remain cold in the low to mid 50s," forecasters said. "Cold water drownings occur each year with these events but are avoidable by remaining a safe distance from the coastline."
Big wave conditions swept two people off beaches in Pacifica in December. A woman was pulled from the waters by a pair of Good Samaritans. Meanwhile, a man was presumed dead after he was was swept away off the rocks near Beach Boulevard and Paloma Ave.
"These large waves can be erratic and unpredictable and may injure or knock beachgoers into the cold, turbulent ocean," forecasters warned.
Among the areas most exposed to the northwest swells are San Francisco's Ocean Beach; San Mateo County's Montara State Beach; Monterey County's Marina State Beach and Monastery Beach in Carmel.
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