Not sure but this might help. I havent used it but I think it links to google map layers and using google maps shows where the various flood zones are and at what height a a certain point floods. If thats not it Im sure is something out there that does this. Might be helpful on planning escape routes based on the best probability of the roads not being flooded.

https://hazards.fema.gov/femaportal/wps/portal/NFHLWMSkmzdownload