High-Resolution Ensemble Prediction

The future of weather prediction will increasingly depend on ensembles of many forecasts, each using differing starting points and model physics.  Such ensembles provide the basis for predicting and defining forecast uncertainty, as well as the provision of probabilities to the forecast.

Most operational ensembles have relatively coarse resolution (typically 25-50  km grid spacing), which is inadequate in places where terrain or convection are important.

Thus, with support from the Northwest modeling consortium and NOAA, the UW has built an operational high-resolution ensemble system, currently with 25 members run at 4-km grid spacing.  This system is not only used operationally, but is a research engine for exploring the influence of high-resolution ensembles and the best ways to post-process their output to provide calibrate uncertainty information.