This paper is concerned with the statistical investigation of a massive data bank of 49 years of rainfall rate

continuously recorded in Barcelona using a rain-rate gauge with ten seconds response time. With radio communications in mind, the paper addresses and reviews in detail: 1) reliable statistical model for

, 2) number of years required to obtain a database from which to derive a reliable

-distribution, and 3) the CCIR worst-month concept. The research has shown that the generalized Pareto

exp

gives nearly perfect fit for all ranges of

followed closely by the gamma distribution, and the simpler square root (

) normal distribution gives excellent fit too. The log-normal distribution was unsatisfactory for

mm/h. The spread of the yearly distribution of

is cube root normally distributed
![([P(R)]^{1/3})](/images/tex/11415.gif)
and between 7 and 10 years are required before a reliable average distribution

can be obtained. The study of the

return time in years is also presented. High resolution of

is presented looking at the evolution of the annual

in terms of the hourly and monthly contributing parts revealing statistical features such as the location in time of rain rates above 50 mm/h. Finally, the study shows that the calendar month contribution to

remains at all times well below the synthetic CCIR worst month and recommendations are then given about its use.