Long-term forecasts
The drought platform’s precipitation forecasts are based on weather simulations in the IFS sub-seasonal model run by the European Centre for Medium-Range Weather Forecasts. This involves simulating possible weather scenarios for the coming weeks. Due to the high level of uncertainty, this type of forecast only allows statements to be made about average weather conditions and not about individual weather events on specific days, in contrast to more familiar weather forecasts. Verification analyses show that forecasts of precipitation trends up to four weeks into the future provide added value compared to climatological forecasts.
The precipitation forecasts integrated here are created from the entire ensemble of 101 weather scenarios in the IFS sub-seasonal model. Because the terrain structure of Switzerland is so complex, the precipitation forecasts are specially reworked by MeteoSwiss in order to improve their quality, especially for the mountain regions. Forecasts for all regions are updated once a day.
These These sub-seasonal forecasts also provide inputs for the hydrological models: from each of the 101 scenarios, a forecast for the conditions of the lakes, watercourses and soil moisture can be created. Like any forecast, hydrological forecasts are subject to uncertainties.
Seasonal forecasts
It is not possible to make weather forecasts several months in advance, but trends in average weather patterns over the coming months can be predicted depending on the situation. Despite significant progress in recent years, the quality of seasonal forecasts for Switzerland remains limited. For this reason, only forecasts for the next four weeks are shown on the drought platform.
Further information: