In the Seasonal Forecasting Engine research project, we combine historical data (ERA5) and trends with seasonal forecasts from multiple dynamical models into probabilistic forecasts. The dynamical model data is provided by the Copernicus Climate Data Store (CDS). The method that we use to combine these data sources will be published soon.
This is our temperature forecast for November, shown as deviation from the long-term climatology in standard deviation units:
The ongoing La Niña is clearly visible as below-normal temperatures in the eastern part of the equatorial Pacific. In most of Europe, above-average temperatures are expected.
When it comes to precipitation, the northern part of Europe is forecast to be slightly wetter-than-normal, but in other regions strongly drier-than-normal conditions are predicted:
Below, the December temperature forecast is shown:
And finally, the combined December precipitation forecast: