England & Wales
In England and Wales live flood information is provided by the Environment agency. On their website you can check flood warnings and river levels and access a 3-day forecast.
Live Flood Warnings
You can also register to have live information sent to you directly.
In Scotland flood information is provided by The Scottish Environment Protection agency (SEPA). You can access live flood information which is updates every 15 minutes or register to have live information sent to you directly.
Live Flood Information for Scotland.
There are quick dial numbers for each region.