California

Durable risk context

• NOAA identifies heavy or extreme precipitation and flooding as relevant planning concerns in California; the type and severity of risk vary by watershed and location.
• Coastal parts of California can face water-level, erosion, surge, or tidal-flood concerns, while inland communities require different local assessments.
• In parts of California, snow accumulation, the share of precipitation falling as rain, and melt timing can affect runoff, water availability, and seasonal flooding.
• NOAA also identifies drought or variable water availability in California; dry conditions do not eliminate short-duration flood or water-intrusion hazards.

Prepare safely

• Know how to receive local warnings, where to find official flood-risk information, and which evacuation or shelter instructions apply to your location.
• If you are in a coastal or surge-prone area, know the local evacuation zone and route before a storm; leave when authorities direct.
• Before seasonal melt or rain-on-snow conditions, keep drainage paths clear where safe and watch official runoff, roof, and river guidance.
• Keep important documents and essential supplies protected, and never walk or drive through floodwater.
• Treat intense rainfall and post-fire or very dry ground cautiously; follow local warnings rather than assuming water will soak in safely.
• After water enters a building, address electrical, structural, and contamination hazards before cleanup or documentation.

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