Safety guides › Flash floods

How dangerous is a flash flood, and what should you do?

Turn around, don’t drown. Six inches of moving water can knock you down.

• Never drive into flooded roads. A foot of moving water can float most cars.
• Six inches of fast-moving water can knock an adult over.
• Floods are most dangerous at night, when you cannot see how deep the water is.
• If water rises around your car, get out and move to higher ground if it is safe.

Source: National Weather Service. Reviewed 2026-10-07.

This guide is general safety information. When a warning is issued for your area, follow the instructions from the National Weather Service and local officials.

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