Plain-English flood knowledge for the UK
Flood risk, explained
before the water rises.
What flood warnings actually mean, how rivers behave, and how to get ready — written simply, backed by live data from FloodRadar.
The one thing everyone should know
Alert, warning, severe — they are not the same thing
Flood alert — be prepared
Flooding is possible in the area, typically on low-lying land and roads near rivers. Nothing may happen — but this is the moment to check your route, your flood kit and the live levels near you.
Flood warning — act now
Flooding is expected for specific properties and roads. Move valuables and vehicles, prepare to turn off gas and electricity, and act on your flood plan — don’t wait to see water first.
Severe flood warning — danger to life
Deep or fast-flowing water is expected. Follow emergency services’ instructions immediately, and be ready to leave your home. These are rare — treat every one seriously.
Guides
Start with the questions everyone asks
Flood alert vs flood warning: what the three levels actually mean
Flood alert vs flood warning explained: what each Environment Agency level means, what to do at each stage, and how severe flood warnings differ.
Weather & warningsWhat 20mm of rain actually means
What 20mm of rain actually means in real terms: litres per square metre, roofs and streets, intensity vs total, and when rainfall totals start to matter for flooding.
ExplainersHow fast can a river rise?
How fast can a river rise? Small becks can rise in under an hour after heavy rain, while big lowland rivers take days. What sets the speed, explained.
ExplainersWhat is surface water flooding?
Surface water flooding happens when rain overwhelms drains — no river needed. Why it is the most common UK flood risk and the hardest to warn for.
Property & buyingHow to check flood risk before buying a house
How to check flood risk before buying a house in the UK: gov.uk long-term risk maps, flood zones 2 and 3, seller disclosure, surveys and insurance.
PreparednessWhat to do when a flood warning is issued
A flood warning means flooding is expected — act now. What to do when a flood warning is issued: people first, move valuables up, and never enter flood water.
Try it
How much rain is a lot of rain?
That’s 20 litres of water on every square metre — about 35 bathtubs on a tennis court.
A properly wet day for most of the UK.
Why intensity matters more than totals →Local briefings