The research behind the forecasts within the S2S4E Decision Support Tool


Several researchers have been involved in improving the forecasts within the S2S4E Decision Support Tool. This work has included combining the forecasts with observational data and analysing past forecasts and how the weather impacts power production and demand. 

“Climate change is expected to lead to more extreme weather and to more frequent extreme weather events, and it is important to take this into account when making predictions about the weather to come over the coming weeks and months,” explains climatologist Irene Cionni.  

Multi-model seasonal forecasts available in the DST


Temperature and wind speed multi-model predictions based on four forecasting systems are now available in the S2S4E Decision Support Tool for 3 months ahead (seasonal forecasts).

The operational tool of the S2S4E project, the Decision Support Tool (DST), offers seasonal forecasts for the next 3 months aimed at the renewable energy sector. Currently, the SEAS5 ECMWF seasonal system is used to generate these predictions.

New study shows quality of river flow forecasts depends on local conditions

River flowing

The quality of seasonal forecasts for flow in rivers in Europe is generally good, but varies depending on local conditions, a recent study by the Swedish Meteorological and Hydrological Institute (SMHI) has found.  

The study was done as part of the EU-funded S2S4E project, and was published in scientific journal Water Resources Research in May. 

Central and Southwestern Europe to see a colder than normal summer

solar energy

The latest forecasts within the S2S4E Decision Support Tool indicate that Central and South-Western Europe could see unseasonably cold weather this summer, researcher Hannah Bloomfield from the University of Reading said on 8 June. 

“June could be relatively cool in Southern Europe, particularly in Spain and Portugal, and there is also a high probability of below normal temperatures for parts of France and Italy,” Bloomfield said during a webinar organised by the EU-funded S2S4E project. 

High snow levels indicate weak power prices in the Nordics this summer


Electricity prices in the Nordic countries are likely to be unusually low this summer amid high inflows to hydropower plants, caused by a combination of a very snow-rich winter and late snowmelt.

“May was cooler than normal in Scandinavia and June has also started on the cool side. This has led to snowpack melting a bit later than it usually does,” Nathalie Schaller, a senior researcher at CICERO Center for International Climate Research, said during a webinar organised on 8 June as part of the S2S4E project.

EUSEW Energy Day: Climate forecasts for renewable energy

webinar series

S2S4E is organising an EUSEW Energy Day on 8 June with a series of three webinars on climate uncertainty visualisation, forecasts for the summer season and the Nordic energy market.

The EU Sustainable Energy Week (EUSEW) is the biggest event dedicated to renewables and efficient energy use in Europe. The 15th edition of EUSEW will be held as a digital event on 22-26 June 2020, bringing together energy stakeholders and enthusiasts to discuss and debate the way forward for green recovery and growth.

Better forecasts could have prevented losses for Swedish hydropower in 2015

Factsheet 4

Very wet weather in Sweden in summer 2015 caused power prices to plunge. The resulting losses for hydropower operators could have been reduced if they had used seasonal forecasts in their decision-making, a study by S2S4E shows.

In the period May-July 2015, precipitation levels in Sweden were well above normal for the time of year, with the rain filling up the country’s hydropower reservoirs. At the same time, it was also unseasonably cold, causing snow melting to occur slower and later than expected