The Ensemble forecast of analyses (EFA) method combines data assimilation and ensemble forecasting to predict future analyses based on current observations. By using a linear combination of ensemble forecasts, EFA can produce accurate predictions of upcoming analyses for various variables and locations. Previous methods lacked uncertainty estimations, but a new approach using a minimax filter now provides both accurate forecasts and uncertainty estimates. This method outperforms traditional models in forecasting peak ozone concentration fields over Europe.