Maps of extreme precipitation

The following maps depict precipitation amounts for extreme events. The spatially comprehensive representation describes the climate of heavy precipitation in Switzerland and illustrates contrasts between regions and seasons. The maps constitute an important knowledge base for the protection against natural hazards.

The graphics represent return levels as a function of return period T. A return level quantifies the amount of precipitation that, in today’s climate and at the location of interest, is exceeded with a probability of 1/T in one year. Additional graphics represent the uncertainty of the estimated return levels. At present, this site depicts results for precipitation sums over the duration of one day.

The analyses were derived from precipitation measurements at 360 stations in Switzerland in the period 1961-2014. In an upcoming update, measurements from more recent years and from the bordering countries will also be integrated. The depicted return levels of extreme precipitation are valid at the point scale. Note that colour scales vary between maps for different return periods.