The comparative snow depth map is published at about 8:30 o'clock. The current snow depth is shown in comparison with the long-term mean value on this calendar day. This is based on measurements from manual measuring sites and automatic measuring stations from SLF and MeteoSwiss, which were collected between approximately 7 am and 8 am. Data transmitted late are continuously integrated into the calculation of the map. In general, data from the 30-year reference period 1991 to 2020 are used to calculate the mean value. Since the measurement series of the automatic stations do not go back that far, all automatically collected data series that have existed at least since winter 2001/2002 are taken into account.
The map is calculated from a distance- and height-dependent interpolation of the measured values. Only regions where enough data points are available are coloured. There is also little data at altitude. Therefore, the few data points above 2500 m are only interpolated depending on distance, but no longer depending on altitude. 100% corresponds to the long-term average on the current calendar day.
The measured values are uncontrolled. It is possible that incorrect values are included in the calculation of the map.
The product is published from 1 December to 15 April.