A rain percentage does not measure water on a road
The probability of precipitation in an hourly forecast is not a prediction of water depth, drainage performance or the condition of a particular crossing. A low percentage at a sampled checkpoint also says nothing definitive about a nearby unsampled road.
Read the official alert, not just its color
An alert includes an affected area, timing and instructions. Read those details in the checkpoint panel and open the official forecast page. Follow emergency instructions; do not use a departure comparison to override a warning or an evacuation order.
An alert check is a snapshot of what has been issued
We check currently active NWS alerts and match their stated timing to your planned arrival. New alerts may be issued later. No matched alert is not a promise that none will apply when you travel. Recheck before departure.
Never use this tool to choose a flooded-road crossing
RoadAheadNow does not measure water depth and is not an emergency routing system. Do not drive into floodwater. Follow the road authority’s closures and the National Weather Service’s flood-safety guidance.
Official sources
National Weather Service flood safety
Reviewed October 5, 2026. Check the current source before travelling.