Even more than in weather forecasts, the skill of seasonal forecasts depends very strongly on the geographical location and season of the year. Also, different forecast systems have strong and weak points in various regions and seasons. For a user of seasonal forecasts it is therefore very important to know what skill the different systems have achieved in past forecasts and hindcasts in order to be able to judge the quality of current forecasts for his/her region.
Verification of seasonal forecasts is available from the various centres (e.g., ECMWF, NCEP, IRI, UKMO) and research experiments (e.g., Demeter). However, these are static pictures, not complete (for all months and lead times) and not directly comparable due to the use of different verification measures and colour scales.
We introduce here the first web site that allows for the dynamic generation of skill score maps and diagrams from a variety of seasonal forecast models using different skill scores.
GJ van Oldenborgh, CAS Coelho. Milestone M5.2: Prototype of an automatic system for forecast quality assessment of seasonal-to-decadal hindcasts