From AMS Glossary
- (Also called frequency curve.) The probability distribution specifying the exceedance probability of different rainfall depths for a given duration (such as 1 hour,
or a 24-hour day).
The exceedance frequency is often reported as a return period (in years), which is the reciprocal of the annual exceedance frequency.
- The expected number of times, during a specified time period, that a given precipitation depth will be exceeded.