PF Map: Contiguous US
· 15min 30min ... Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. ... The precipitation frequency estimates were derived from annual maximum series at each station in the region (as described in documentation). Results are provided for 60min, 24hr, 2day, and 10day durations and for annual exceedance probabilities of 1/2 (or 1in2), .