San Francisco weekend weather: Smoke, dangerous beaches, heat

OAKLAND, Calif. - Several weather hazards are lining up across the Bay Area heading into the weekend, from wildfire smoke and dangerous beach conditions to increasing inland heat and elevated fire weather concerns.

Here’s what residents should know before making weekend plans.

Spare the Air Alert issued

The Woodside Fire in Sonoma County has prompted a Spare the Air Alert for the Bay Area for Friday. Smoke may create hazy skies and reduce air quality, particularly in the North Bay and other communities downwind of the fire.

People with asthma, heart or lung disease, older adults and young children should limit prolonged outdoor activity if smoke becomes noticeable. Everyone can help reduce pollution by limiting driving, avoiding backyard burning and postponing the use of gas-powered lawn equipment.

Beach hazards 

A Beach Hazards Statement remains in effect through Saturday at 5p.m. along the Bay Area coastline. Long-period swells generated by tropical systems in the eastern Pacific continue to produce dangerous ocean conditions, including:

Sneaker waves that can surge far up the beach without warning. Powerful rip currents capable of pulling swimmers offshore.
Large waves can sweep people from rocks, jetties and coastal trails.
Beachgoers are urged to stay well back from the surf, never turn their backs on the ocean and closely supervise children near the water.

Inland heat

High pressure over the Desert Southwest will continue strengthening into California, bringing a gradual warming trend through the weekend.

Inland valleys will experience the hottest temperatures with a moderate heat risk, while coastal communities remain significantly cooler thanks to the marine layer. Residents spending time outdoors should stay hydrated, take frequent breaks and check on older neighbors, family members and pets.

Fire weather

Forecasters are also watching a period of gusty offshore winds late Saturday night into Sunday morning.
While the strongest winds are expected over the coastal waters, dry northeast winds moving into portions of the North and East Bay hills could combine with low humidity to increase wildfire danger.
Residents living in fire-prone areas should remain aware of changing weather conditions and avoid activities that could accidentally ignite a wildfire.

Strong marine wind

The National Weather Service is also forecasting a powerful marine wind event over the northern California coastal waters this weekend. Gale-force winds and building seas are expected to create hazardous conditions for boaters.

The event, developing late Saturday into Sunday, is not being driven by Tropical Storm Genevieve. While Tropical Storm Genevieve continues to generate long-period swells responsible for hazardous beach conditions along the California coast, the strong marine winds are expected to develop as strong high pressure builds over the eastern Pacific while lower pressure develops inland over California, creating a steep pressure gradient accelerating northwest winds over the coastal waters.

The same weather pattern may also usher drier air into portions of the North and East Bay hills, briefly increasing fire weather concerns Sunday morning, although the strongest winds are expected to remain over the ocean.
 

Weather