Weather & Natural Hazards
Flooding & flash floods
Flooding is survivable when you give water room. Learn the depth rule, warning types, and trapped-car steps.
Flooding is one of the nation's deadliest weather hazards, and many flood deaths happen in vehicles — people who drove into water that was deeper or faster than it looked. The rule that saves the most lives is the simplest: Turn Around, Don't Drown.
The single most important rule
Turn Around, Don't Drown
Turn Around, Don't Drown: never walk or drive into floodwater. You can't tell how deep it is, how fast it's moving, or whether the road beneath it has washed away. Turn around and find another route — every time.
Why water beats the car
How deep is too deep
As a rule of thumb (not an exact promise for every vehicle): about 6 inches of fast-moving water can knock an adult off their feet; about 12 inches can float many cars; and 18 to 24 inches will carry off most vehicles, including trucks and SUVs — and the roadbed underneath may already be gone.
Fast and local, or slow and forecast
Two kinds of flooding
There are two kinds of flooding. A flash flood is fast and local — water can rise in minutes, especially in the Ozarks, at low-water crossings, and in small creeks and dry washes after heavy rain. River flooding is slower — it builds over days as a river rises, and the Weather Service forecasts it river by river. (Floating or near a river? See the Rivers & Tubing hub for low-water crossings and reading river levels.)
If you spend time on or near the water, the Rivers & Tubing hub goes deeper on low-water crossings and river gauges.
What the warnings mean
Two flood warnings, two responses
Flash Flood Warning
A Flash Flood Warning means move to higher ground NOW — the water can come up faster than you can react.
River Flood Warning
A River Flood Warning means follow the forecast, the evacuation instructions, and the road closures for that specific river. A slow-rising river doesn't mean everyone must instantly climb to high ground — follow the location-specific instruction the warning gives.
If water reaches your car
If your car is trapped in floodwater
If floodwater traps your vehicle, never step out into rapidly moving water — it can sweep you off your feet and pull you under. If fast water is around the car, STAY INSIDE. If water starts rising INSIDE the car, get onto the roof and call or signal for help. Move on foot only if the water around you is shallow and still. And never drive around a barricade — it's there because the road ahead is unsafe or gone.
On foot and afterward
Other flood rules
Don't camp or park in low spots or dry creek beds when heavy rain threatens. Stay out of floodwater on foot — it can be deep, fast, full of debris, and even electrically charged by downed lines. After a flood, wait for officials before you go back, and never trust a flooded road.
A benchmark Missouri remembers
Missouri's great flood
Missouri's benchmark is the Great Flood of 1993. The Mississippi River at St. Louis crested at 49.58 feet on August 1, 1993 — about 20 feet above flood stage. Across the multi-state disaster, damage ran to roughly $15 billion and about 50 people died.
A money note
A money note, not advice: standard homeowner's and renter's policies usually do NOT cover flood damage — that's a separate policy through the National Flood Insurance Program (NFIP) or a private insurer, and NFIP coverage typically has a 30-day waiting period before it starts (with limited exceptions). Ask a licensed agent before flood season, not during it.
Next
A flash flood can rise fast. Make sure alerts can reach you at night. A NOAA Weather Radio can wake you for a 3 a.m. warning. If you spend time on the water, float trips start at the Rivers & Tubing hub.
Flood questions people ask first
How much water is too much to drive through?
Treat any water over the road as too much. You usually cannot see whether the road is still there, how deep the water is, or how fast it is moving.
Is a flash flood different from a river flood?
Yes. A flash flood can rise fast and close a road or low-water crossing with little time. A river flood often has more forecast lead time, but it can last longer.
Do regular home policies cover flooding?
Do not assume that. Flood insurance is its own question, so use FloodSmart or your insurance agent for that answer.
Where do I check river levels?
Use the National Weather Service for flood products and river forecasts. For float trips and low-water crossings, open the river-level guide too.
Page feedback
See something off, missing, or unclear?
Send a quick note if a source, local detail, or answer needs a closer look, or if the page leaves you with a question.
Page feedback
Send a note
The page you're on will be included automatically.