MAP - HIT RATE (POD - Probability Of Detection)
Hit rate indicates fraction of the observed events (flood watch stage exceeding) which were correctly forecasted.

Equation: POD = H/(H+M)

where H is number of HITS and M number of MISS forecasts. Range: 0 to 1. Perfect score: 1. Because it ignores number of FALSE ALARMS Hit rate can be close to perfect score when an event is systematically overforecasted.