Know your alerts
Flood Warning vs Flood Watch
A flood watch means conditions are favorable for flooding. A flood warning means flooding is happening or imminent. The difference is urgency — and your response should match.
The watch
What a flood watch means
The National Weather Service issues a flood watch when conditions are favorable for flooding. It does not mean flooding will occur, but it is possible. A watch is your signal to prepare: know the fastest way to higher ground from home and the roads you use, charge your phone and portable radios, pack essentials in advance in case you need to evacuate, and stay informed.
If it is likely your home will flood, don't wait to be ordered to leave — evacuate yourself.
The warning
What a flood warning means
A flood warning means flooding is imminent or already happening in the warned area. When a warning is issued, act: move to higher ground immediately if you are in a flood-prone area, and if you are told to evacuate, do so immediately.
Never drive through flooded roads. Turn around, don't drown — just 6 inches of fast-moving water can knock over an adult, 12 inches of rushing water can carry away most cars, and 2 feet can carry away SUVs and trucks. The road under the water may have collapsed.
At a glance
The four flood alerts at a glance
| Alert | Meaning | Your action |
|---|---|---|
| Flood Watch | Conditions are favorable for flooding; it is possible, not certain | Prepare, stay informed |
| Flood Advisory | Flooding expected, but not bad enough for a warning — it can still cause significant inconvenience and become dangerous | Be aware, use caution |
| Flood Warning | Flooding is imminent or occurring | Move to higher ground now |
| Flash Flood Warning | A flash flood is imminent or occurring | Move to higher ground immediately |
Flash floods
Flash flood vs. regular flood
A flash flood is a sudden, violent flood that can take from minutes to hours to develop — generally within 6 hours of its cause, usually intense rainfall. It can even strike areas that are not receiving rain. Flash flood warnings are issued when a flash flood is imminent or occurring.
Urban areas are especially prone because concrete and asphalt don't let water soak in; steep terrain sends runoff into streams quickly; and wildfire burn scars leave ground that repels water.
Stay informed
How to check current flood alerts
The National Weather Service publishes all active alerts at weather.gov, and NOAA Weather Radio broadcasts them. During hurricane season, our live Atlantic storm tracker shows active systems that could produce flooding rainfall. For river-level flooding near you, check USGS real-time stream gauges.
FAQ
Common questions
What is the difference between a flood watch and a flood warning?
A flood watch means conditions are favorable for flooding, but it has not started. A flood warning means flooding is happening now or is about to. A watch tells you to prepare; a warning tells you to act.
How serious is a flood warning?
A flood warning means flooding is occurring or imminent. Move to higher ground immediately if you are in a flood-prone part of the warned area, and never drive through flooded roads.
What should I do during a flash flood warning?
Move to higher ground immediately — flash floods can develop in minutes. Never drive through flood water: 6 inches of fast-moving water can knock over an adult, and 12 inches can carry away most cars.
Where can I see active flood alerts for my area?
Visit weather.gov and enter your location, or monitor NOAA Weather Radio. During hurricane season, HurriTrack's live tracker shows storm systems that could produce flooding.
Next
Hurricanes bring two kinds of water — see storm surge vs. flooding. Get ready with the hurricane prep checklist, and learn the wind alerts in hurricane watch vs. warning.
Sources
Every safety-critical and quantitative claim on this page is drawn from these primary sources. Guidance can change — follow your local emergency management for decisions where you are.
- Flood Watch vs. Flood Warning — NOAA / National Weather Service. https://www.weather.gov/safety/flood-watch-warning
- Turn Around Don't Drown — NOAA / National Weather Service. https://www.weather.gov/safety/flood-turn-around-dont-drown
- Flood Hazards: Flash Flooding and Burn Scars — NOAA / National Weather Service. https://www.weather.gov/safety/flood-hazards
- Before a Flood — NOAA / National Weather Service. https://www.weather.gov/safety/flood-before
- During a Flood — NOAA / National Weather Service. https://www.weather.gov/safety/flood-during
HurriTrack is an independent guide for general awareness and is not an official source. For any safety decision, follow NHC, the National Weather Service and your local emergency management.