When is the flood coming?
When extreme rain events occur, the National Weather Service will issue flood watches and warnings based off of the predicted flood stage at a stream gauge. These gauges are physically located in a river and give automated, near real-time information on water depth and flow. This data is combined with observed rainfall, predicted rainfall and snowmelt to create a flood prediction Hydrograph (see example below) that estimates the Stage (ft) and Flow (cfs) for the next 5-7 days.