Rain events can be described in terms of point processes, analogously to other geophysical phenomena, such as earthquakes or avalanches. Power-law behaviors have been identified in the distribution of sizes, of rain event durations and drought durations, with scaling exponents 1.4, 2.4 and 1.3, respectively. Time-fractal approaches, like Fano Factor and Allan Factor, well suited to reveal scaling behavior in point processes, allow to detect power-law behavior in rainfall data, pointing out to the presence of clustering in the time distribution of the sequence of rain events.