Flood.global app and flood alerts
Add Flood.global to your phone's home screen, save your home in it, and get a notification when a flood alert is issued for your home or a river you choose rises toward flood stage.
Reviewed October 2026
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What you get
- Your home, one tap away. Flood.global opens straight to your saved home: its FEMA flood zone, flood alerts in effect and nearby river levels. If you're offline, it shows the last check.
- Flood alerts for your home. A notification when the National Weather Service issues a flood-related watch, warning, advisory or emergency for your location, including flash flood, coastal flood, storm surge, hurricane and tropical storm alerts.
- River level alerts. Pick up to three nearby river or tide gauges. You'll get a notification when one rises to its action level or into minor, moderate or major flooding, when NOAA forecasts it to flood, and an all-clear when it's back to normal.
It's free, there's no account to create, and it runs in your phone's browser engine, so there's nothing to download from an app store.
How to set it up
- Add Flood.global to your home screen.
- iPhone or iPad: in Safari, tap the Share button, then Add to Home Screen. Alerts need iOS or iPadOS 16.4 or later.
- Android: in Chrome, tap Install app when it's offered, or open the ⋮ menu and choose Add to Home screen or Install app.
- Computer: in Chrome or Edge, use the install icon in the address bar. You can also save your home and turn on alerts in most desktop browsers without installing.
- Open Flood.global from your home screen and look up your address.
- Tap Get flood alerts here, then Allow. That saves the address as your home and turns on alerts in one step: National Weather Service flood alerts for your home, plus the nearest river gauge with flood levels within 10 miles, if there is one. To pick different gauges, choose Change alerts afterwards.
On iPhone and iPad, look up your address inside the app even if you already did in Safari: they keep home screen apps separate from Safari.
On iPhone and iPad, notifications only work when you open Flood.global from its home screen icon, not from a Safari tab. If you choose Don't Allow by mistake, remove the icon from your home screen, add it again and turn alerts on again.
How the alerts work
Every 30 minutes, Flood.global checks the National Weather Service for active alerts at your saved home and NOAA's National Water Prediction Service for the gauges you chose. It sends a notification only when something changes:
| Notification | When it's sent |
|---|---|
| Flood alert | A new type of flood-related alert starts for your location. Updates and extensions of an alert that's already in effect don't notify you again. |
| River rising | A gauge you watch rises to its action level (near flood stage), or into minor, moderate or major flooding. Each level notifies once. |
| Flooding forecast | NOAA forecasts a gauge you watch to reach minor flooding or worse. |
| Back to normal | A gauge that was at its action level or higher has dropped back below it on two checks in a row. |
To see what each alert and flood level means, read flood alerts explained and how to read river flood stages.
Don't rely on it alone
Flood.global alerts are a free extra, not an official warning system. Because we check every 30 minutes, an alert can reach you up to about half an hour after the National Weather Service issues it, and longer if a service is down or your phone is offline, in low power mode or has notifications silenced. Flash floods can happen faster than that.
- Keep Wireless Emergency Alerts turned on in your phone's settings. These come straight from officials and reach phones within minutes for the most dangerous warnings.
- Use a NOAA Weather Radio if you live in a flood-prone area, especially for warnings at night.
- Follow instructions from local officials, and never drive or walk into floodwater. How to prepare for a flood
Privacy
When you turn on alerts, we store your phone's notification address (a random web address from Apple, Google, Mozilla or Microsoft that lets us send to your device), your saved home's location rounded to about 100 meters (330 feet), the gauges you chose and your time zone. We never store your street address: it stays on your device. Details are in our privacy policy.
Turning alerts off
Open Flood.global from your home screen and choose Turn off alerts. Removing the home screen icon, or blocking notifications for Flood.global in your phone's settings, also stops them; we delete a device's details the next time a notification to it fails.