The upper-level storm system responsible for the Bay Area’s gusts has moved inland over the Rocky Mountains, causing temperatures to rise across much of the region on Thursday and winds to ease considerably.

On the backside of the storm, sustained winds of 10 to 15 mph, with higher gusts, are blowing from the north-northwest, across the Sacramento Valley and through the hills of the northern and eastern bays. The air mass dries out during the afternoon.

That combination of offshore winds and falling relative humidity is creating a slightly increased fire risk in the foothills north of the Sonoma and Napa valleys, as well as in the inland foothills of the East Bay and east of Mount Diablo.

The inland wind direction of the coast also increases the chance that smoke from multiple fires in Oregon will blow into the region later this afternoon and evening.

The inland current will keep temperatures in San Francisco and along the coast around 17 to 21 degrees Celsius, but outside the water temperatures will rise to 27 to almost 32 degrees Celsius, noticeably warmer than yesterday.

This warming inland will continue until Friday at least, after which there will be a significant cooling over the weekend, with temperatures dropping by around 10 to 15 degrees on Sunday.

San Francisco: Low clouds will hang over the city in the morning, giving way to partly sunny skies by late morning and early afternoon. Winds will pick up from the west at 10 to 20 mph with some higher gusts in some pockets of terrain. High temperatures will be in the mid 60s in the Sunset and Mission neighborhoods, with highs in the upper 60s to around 70 degrees downtown. Clouds will return over most of the city by evening and overnight, with calmer winds and temperatures in the low to mid 50s.

North Bay: Early morning clouds will extend from the coast to the Petaluma Valley, but will clear quickly. Mostly sunny and warm with highs in the low to mid 80s in Napa, Petaluma, Novato and Santa Rosa. Winds will be from the north-northwest at 10 to 15 mph with higher gusts over the elevated terrain around Napa and Sonoma. Partly cloudy tonight with less wind and temperatures in the 50s.

East Bay: Low clouds along and west of the Berkeley Hills will clear by mid-morning, making it a mostly sunny day across the region. Highs will be in the 70s in Richmond, Oakland, Hayward and Fremont with a light west wind of 5 to 15 mph. It will be much warmer inland, with highs in the mid to high 80s in Concord, Dublin and Tracy. Winds across the inland hills around Mount Diablo will be from the north-northeast at 10 to 15 mph with higher gusts. Some air quality deterioration may occur around Concord and back inland in places like Brentwood as wildfire smoke drifts in from the Pacific Northwest. Mostly clear tonight with lows in the mid 50s.

Pacific coast and peninsula: It will be a windy and cloudy start for the Pacific Coast, with some partly clearing in the afternoon. Highs will be in the mid to upper 60s in Pacifica, Half Moon Bay and Daly City, with west winds of 10 to 20 mph. Sunshine will develop more quickly over the rest of the peninsula, with highs in the low to mid 70s in South San Francisco and SFO and highs in the low 80s in Redwood City. Winds will be west at 10 to 20 mph. Partly cloudy tonight with lighter winds and lows in the 50s.

South Bay and Santa Cruz: Sunny skies will develop early this morning across the South Bay, and temperatures will warm to the low to mid 80s in Palo Alto, San Jose, and Gilroy. Winds will be breezy out of the north-northwest at 5 to 15 mph. Mostly sunny throughout Santa Cruz as well, with highs in the upper 70s in Santa Cruz and highs in the low 80s in the hills. Mostly clear tonight with lows in the upper 50s to low 60s.

Contact Greg Porter: [email protected]