Chileno

Forward progress stopped as crews mop up hot spots west of Petaluma

The Chileno Fire is burning in grass and pastureland near Chileno Valley Road and Bordessa Road in northern Marin County, west of Petaluma. Firefighters halted the fire's forward progress on Sunday, and coastal fog and cool weather have assisted crews in extinguishing lingering hot spots. The fire poses no direct threat to Petaluma or surrounding populated areas.

Evacuations and Closures

• No evacuation orders or warnings are in effect as of September 21; an initial evacuation advisory for zone MRN-E118 in Chileno Valley was lifted.

Impact

No homes or other buildings have been damaged or destroyed, though agricultural properties sustained damage to pasture fencing, water lines, and grazing land. Smoke prompted air quality advisories across southern Sonoma and Marin counties. Officials reported zero injuries or fatalities as of September 21.

Conditions and Outlook

Light to moderate westerly to southwesterly winds will continue over the next few days, accompanied by morning fog, drier afternoon conditions, and no chance of precipitation. Fire activity is expected to remain minimal with no additional spread. Firefighters will continue patrolling the perimeter and mopping up interior heat.

Cause and Context

The cause of the fire remains undetermined and under investigation by the Marin County Fire Department as of September 21.

Official updates current through September 22, 2026.