Flood warnings data for England
The Environment Agency issue warnings of floods that cover specific warning or alert areas. The floods API provides a listing of all current such warnings and is updated every 15minutes.

A warning may be at one of four possible severity levels:

1 Severe Flood Warning: Severe Flooding, Danger to Life.

2 Flood Warning: Flooding is Expected, Immediate Action Required.

3 Flood Alert: Flooding is Possible, Be Prepared.

4 Warning no Longer in Force: The warning is no longer in force

this uses Environment Agency flood and river level data from the real-time data API (Beta)

If no data appears, this is because there have been no flood warnings issued for Cambridgeshire. For all flood warnings please see the Environment Agency's Flood Warning page.

More details available at: http://environment.data.gov.uk/flood-monitoring/doc/reference#api-requests