The animated layer shows precipitation accumulations forecasted for the upcoming five days, with leadtimes from 0-120h. Forecasts for lead times out to six hours are hourly, and six-hourly thereafter. ~80th percentile~
These precipitation accumulations have been obtained by seamless blending of the:
(i) 20-members ensemble of 1-h accumulation generated with the algorithm for probabilistic nowcasting by extrapolation of radar observations SBMcast (Berenguer et al., 2011) applied to the gauge-adjusted OPERA radar composites over Europe (2 km, 15 minutes; Park et al. 2019)
(ii) 51-members ensemble of 1-h accumulation forecasts obtained by Numerical Weather Prediction with the ECMWF Ensemble Prediction System (EPS).
The blending technique (Wong et al. 2009) is applied for the first 6 hours, and applies a phase shift and bias correction to blend radar nowcasts into NWP using a hyperbolic tangent weighting function. For lead times beyond 6 hours, the product relies only on the NWP forecasts.
The displayed accumulations correspond to the forecasts obtained with the control member