Red Flag Warning, strong winds and dry air raise fire danger in Fresno County

Dry winds and critically low humidity put Fresno County under a Red Flag Warning, with the highest fire danger across the San Joaquin Valley, the West Side Hills of the Coastal Range and other low-elevation zones in central California. The National Weather Service office in Hanford said the warning was in effect through Monday evening, and its Fresno-area forecast page listed it until 8 p.m. PDT Monday, May 18, 2026.

Forecasters said northwest flow behind an upper-level trough was pushing through the region, creating a 60% to 70% chance of gusts topping 30 mph in western valley areas. That wind, combined with afternoon relative humidity near 15% to 20% in the western valley and minimum humidity below 15% across much of the San Joaquin Valley on Monday, created what forecasters called a major risk for fire danger across central California.

For Fresno County, that meant the areas most likely to see a fast-moving grass fire were the dry, open stretches west of Fresno, the valley floor and foothill edges where brush and cured grass can carry flame quickly. The threat was not limited to one neighborhood or road corridor. The Hanford forecast area spans 21 zones across valley, mountain and desert climates and includes Fresno County, underscoring how quickly a wind-driven spark can move across rural ground, orchards and roadside vegetation.

Residents were urged to follow local burn bans, avoid mowing dry grass and keep brush cleared away from homes and outbuildings. Drivers were also warned to watch for vehicle parts or chains dragging on roads, a common ignition source when roadsides are dry and winds are strong. For people planning weekend travel, the combination of gusty wind and very low humidity meant any roadside spark could turn into a fast grass fire with little warning.

Fresno County Fire Protection District said residents should check evacuation status through the Fresno County Sheriff’s Office mapping system, which uses green for no evacuations, yellow for an evacuation warning and red for an evacuation order. The district said the map works the same way as the system used during the Creek Fire. An evacuation warning means there is a potential threat to life or property, and people who need extra time, including those with pets or livestock, should leave immediately.

The district also said residents can sign up for Everbridge alerts by email, voice or text. During a fire, the Central California Animal Disaster Team can help transport animals, a step that matters for ranches, small farms and horse owners across Fresno County when minutes count.