Northern California is under active Red Flag Warnings stretching from Redding south through the Sacramento Valley and across to the San Francisco Bay Area, with critically dry and gusty conditions that have already contributed to an active wildfire in Yolo County — and prompted Governor Newsom to preposition a major firefighting force across six counties ahead of the worst conditions.
Red Flag Warnings Active Across a Wide Zone
Three NWS offices — Sacramento, San Francisco and Eureka — have active Red Flag Warnings covering a broad reach of the region. The Sacramento office has a warning through 5 PM PDT Thursday for the northern Sacramento Valley, covering Shasta, Tehama, Glenn, Colusa, Butte, Sutter, Yuba, Yolo and Solano counties.
The San Francisco Bay Area office has a warning through 9 AM Thursday for the North Bay Interior Mountains and East Bay Hills — including parts of Alameda, Contra Costa, Lake, Napa, Sonoma and Solano counties. The Eureka office has warnings through Thursday evening for southeastern Lake County, including Clearlake, Middletown, Cobb and the Konocti area.
North winds of 15 to 25 mph with gusts reaching 40 to 45 mph are forecast throughout the warning period, with ridge tops possibly seeing gusts around 60 mph according to CBS San Francisco. Daytime relative humidity is dropping to between 9 and 15 percent — conditions where any fire start could spread quickly and become difficult to control, CAL FIRE warned. The highest threat area is along and west of the I-5 corridor in the Sacramento Valley.
A Fire Is Already Burning in the Warning Zone
The concern is not theoretical. The Putah Fire in Yolo County — 869 acres and 30 percent contained as of Wednesday morning — was burning inside the warning zone before conditions even peaked.
The fire sparked June 8 when a prescribed burn escaped control lines near Winters, closing Highway 128 before partial reopening. Fire crews were already engaged on the blaze as Red Flag conditions intensified Wednesday, according to Redheaded Blackbelt reporting.
Governor Deploys 100+ Fire Crews Ahead of Peak Conditions
At the direction of Governor Gavin Newsom, Cal OES prepositioned 26 fire engines, nine water tenders, one helicopter and more than 100 personnel to Colusa, Glenn, Lake, Napa, Tehama and Yolo counties Wednesday. “California is facing elevated wildfire risk and extreme heat in the days ahead,” the governor’s office stated, adding that state agencies are coordinating with local partners and monitoring conditions around the clock.
Cal Fire Humboldt-Del Norte units also repositioned south into the Sacramento Valley — a prepositioning strategy that stages crews in high-risk areas before fire weather peaks, cutting response times if a new ignition occurs.
PG&E Power Shutoffs Begin
The Red Flag Warning has triggered a public safety power shutoff across multiple Northern California counties. Pacific Gas & Electric warned that customers in several counties will likely see outages Wednesday and Thursday, as the utility cuts power to lines in fire-prone areas to reduce ignition risk from downed or sparking equipment.
Residents in affected zones should charge devices now, prepare go-kits with essential documents and medications, and review evacuation routes. For the latest fire weather updates, check weather.gov/sto and readyforwildfire.org. If you see smoke or fire, call 911 immediately — do not wait to confirm.
