SACRAMENTO -- The National Weather Service has issued a Red Flag Warning for a large portion of Northern California, including the Sierra foothills, Sacramento Valley, Delta and Bay Area hills.
The time of greatest concern will be between Tuesday and Wednesday morning when gusty north winds will combine with low humidities. Winds will be especially strong on the western side of the Sacramento Valley.
In preparation for the conditions, Cal Fire is staffing additional aircraft, engines, hand crews and bulldozers, positioning them strategically statewide, according to Cal Fire Deputy Director Chief Mike Mohler.
Even though temperatures are cooler compared to summer, fires can still spread rapidly due to the combination of wind, low humidity and critically dry vegetation.
Mohler urges everyone in the red flag areas to stay alert and have a fire evacuation plan.
Cal Fire says 95 percent of wildland fires are human-caused.
Members of the public are advised to suspend all outdoor burning and avoid operating mowers and other machinery in dry grass. Vehicles should be checked for low hanging equipment or chains that could cause sparks. Cigarettes should not be thrown out car windows.
Some of California's most devastating fires, including the 1991 Oakland Hills Firestorm and last year's Tubbs Fire in wine country, broke out in October during similar weather patterns.