Flooding
River Flood Warning Explained: Crest, Gauge, and Flood Stage
How river flood warnings work, what flood stage and crest mean, and why rivers can keep rising after rain ends.
Quick answer: A river flood warning means a river or stream is expected to exceed flood stage or is already flooding.
Flood stage
Flood stage is a gauge level where water begins to cause impacts in that area. It is not the same everywhere.
Minor, moderate, and major flood categories describe increasing impacts.
Crest timing
A crest is the highest level expected during an event. Rivers can keep rising long after the heaviest rain stops because water drains downstream.
Forecast crests can change as new rain falls or upstream flows arrive.
Safety
Do not drive through flooded roads near rivers. Water can hide washed-out pavement and strong current.
Respect closures and give levees, bridges, and flooded banks plenty of space.