The Met Office is stating that there is a risk of heavy thunderstorms in Cambridgeshire today (26th July) and tomorrow (27th July) which could cause notable surface water flooding. The cause is from slow moving showers across the County. You can see the warning details for both days here: https://www.metoffice.gov.uk/public/weather/warnings#?date=2018-07-26
The issue with ‘slow moving’ showers is that it is very difficult to state where exactly and when exactly the rainfall will, if at all, fall within the County. If it does fall within an isolated area of the County we could experience flooding like that in August, 2014 where a number of major roads were closed and properties flooded.
The risk from rivers remains very low and there is no anticipation of the issuing of any widespread flood alerts or warnings for river flooding – you should sign up to the Environment agency’s flood alerts and warnings for more information on this. You can do so here: https://www.gov.uk/sign-up-for-flood-warnings
With the weekend approaching a contacts list that may be of use to you and other residents as to where to turn for assistance is here: Flooding advice emergency contacts – July 2018