The North Bay is bracing for its first severe fire weather event of 2026, as a red flag warning takes effect Thursday, June 11, amid a heat wave that is expected to push temperatures near triple digits. The warning, issued by the National Weather Service, begins at 11 p.m.
Wednesday and extends into Thursday morning, marking the first such alert for the region this year. It coincides with a heat advisory covering most of the North Bay, including Sonoma and Napa counties.
Meteorologist Rachel Kennedy of the National Weather Service said the strongest winds are expected overnight, with sustained speeds of 35 to 40 mph and gusts up to 60 mph, while relative humidity drops into the low teens. These conditions create a high risk for rapid wildfire growth.
The heat wave, which began Wednesday, is forecast to peak Thursday, with temperatures reaching 98 degrees at Charles M. Schulz-Sonoma County Airport north of Santa Rosa.
In Cloverdale, the high is expected to hit 100 degrees, and Healdsburg could see 101. Napa is forecast to reach 97 degrees, while St.
Helena may hit 100. Coastal and bayshore areas will be slightly cooler, with Petaluma at 95 degrees and Sonoma at 99.
Although the red flag warning is expected to end Thursday, Kennedy warned that relative humidity will remain low, urging residents to stay vigilant. Fire officials have cautioned those working outdoors to be aware of their surroundings and the risk of equipment sparking a wildfire.
Pacific Gas & Electric Co. (PG&E) is monitoring conditions and may implement preemptive power shutoffs to reduce the risk of its electrical equipment igniting a blaze.
Other counties, including Lake, Yolo, Colusa, Glenn, Sutter, and Tehama, are under a higher-level warning from PG&E, with shutoffs expected.
Despite the widespread heat advisory, Sonoma County’s Department of Emergency Management said county-operated cooling centers will not open because forecast conditions have not met the county’s threshold for activation, which typically requires at least three consecutive days of extreme heat. Unless temperatures rise unexpectedly during the day or fail to drop at night, this week’s heat wave is not expected to meet that threshold.
However, PG&E announced plans to open community resource centers in Sonoma and Napa for residents affected by outages or seeking relief from the heat. In Sonoma, a center will operate from 6 to 10 p.m.
at First Congregational Church of Sonoma, 252 W. Spain St.
In Napa, a second center will open during the same hours at Napa Elks Lodge, 2840 Soscol Ave. Cloverdale city officials announced a cooling center will be open from 11 a.m.
Thursday at La Familia Sana Resiliency Center, 437 N. Cloverdale Blvd.
These sites will offer refreshments, food, and relief from the heat. PG&E community centers will also provide portable batteries, ADA-accessible restrooms, and washing stations, but electric vehicle charging will not be available.
Service animals are permitted.
Residents are urged to take precautions to reduce wildfire risk, including properly disposing of cigarettes and matches, avoiding equipment that can create sparks, ensuring campfires are fully extinguished, and following local burn bans and permit requirements. Santa Rosa officials reminded those using trailers to secure them properly so tow chains do not drag and cause sparks.
Anyone operating outdoor equipment should use extra caution, and landscaping work in highly flammable areas should be avoided until conditions improve. Residents who see smoke or signs of fire should immediately call 911.