1-min rain rate statistics predictions from 1-hour rain rate statistics measurements

A new method is presented, which allows the recovery of the cumulative distribution function (CDF) of point rain rate with 1-min integration time (P(R)1) from rain rate CDFs with longer integration time (in this case, 1-hour time average rain rate statistics (P(R)60). The method generates the scaling factors between (P(R)60) and (P(R)1) as a function of the probability level and of the site geographical coordinates. From the scaling factors, a scaling law of the form proposed by Chebil and Raman is devised. The method is applicable worldwide and produces predictions far more accurate than the ones provided by general P(R) estimation techniques.