Wildfire preparedness in San Mateo County runs in a specific order: personal safety and evacuation readiness first, then hardening your home against embers, then defensible space around it. Each layer protects the ones behind it.
1. Be Ready to Leave
Register for alerts, know your zone, plan your evacuation. Life safety comes before property, every time.
Evacuation Preparedness
2. Harden Your Home
Embers ignite most homes. Close the pathways: roof, vents, windows, deck, fence, and the first 5 feet.
Home Hardening
3. Create Defensible Space
Zones 0, 1, and 2 reduce fire intensity, remove ember fuel, and give firefighters a defensible position.
Defensible Space
Know Your Hazard
The State Fire Marshal's Fire Hazard Severity Zone maps, updated in 2024 and 2025, expanded designated zones across San Mateo County. Your zone determines defensible space enforcement, building standards, and disclosure requirements. Look up your address on the official FHSZ maps.
Red Flag Warning Days
The National Weather Service issues Red Flag Warnings when offshore "Diablo" winds, critically dry fuels, and low humidity align: the conditions under which fires grow explosively. When a Red Flag Warning covers San Mateo County:
Don't
- No outdoor fires or fire pits of any kind.
- No outdoor use of spark- or heat-producing equipment: mowers, string trimmers, chainsaws, grinders, welders, torches, or outdoor cooking with open flame.
- Do not drive or park on dry grass or vegetation.
Do
- Review your evacuation checklist and keep go-kits at hand.
- Walk the outside of your house and move anything combustible (furniture cushions, doormats, potted plants, woodpiles, debris) inside or at least 30 feet from structures.
- Clear leaves from the roof, gutters, and the base of walls.
- Close windows and skylights if you leave town.
- Fuel or charge your vehicle and park it nose-out, outside the garage; open automatic gates in case power fails.
- Charge your phone and monitor alerts. Report dangerous activity to SMC non-emergency dispatch at (650) 363-4963, or 911 for fires.
Stay Informed
- SMC Alert — the county's official emergency notification system. Register every device.
- Genasys Protect — evacuation zone lookup and status.
- Watch Duty — real-time wildfire mapping and alerts.
Get Recognized for Your Preparedness
Wildfire Prepared Home (IBHS)
The Insurance Institute for Business & Home Safety's Wildfire Prepared Home program is a research-based standard and third-party-verified designation covering the hardening and Zone 0 measures that most determine survival, and it qualifies for insurance recognition under California's Safer from Wildfires regulation. Start with the homeowner guide: Wildfire Prepared Home standard homeowner guide (PDF).
Firewise USA Recognition
Neighborhoods that organize can earn Firewise USA recognition, which structures community risk reduction and also counts toward insurance discounts. See the recognition process overview: Firewise recognition procedures (PDF), and our fire-safe communities page for local support.
