On the applicability of temporal stability analysis to raingauge network design

Determining “representative” rain gauge stations over a wide area is useful to optimize an existing rain gauge network, design a network in ungauged basins and calibrate a meteorological radar by ground measurements. Most available methodologies have been developed for specific watersheds and cannot be objectively transferred to other regions. This issue is addressed here through a reformulation of the temporal stability analysis for the areal-average cumulative rainfall depth, R, of single meteorological systems and an evaluation of its efficiency for application to common typologies of frontal systems with different physical characteristics. On this basis, our results suggest that, in each watershed, the combination of the measurements performed in the two stations with better ranking gives a fairly good representation of R derived from all the operative rain gauges, particularly for significant frontal systems, with the magnitude of the relative error generally less than 10%.