Advances in Subseasonal Prediction of 100 m Wind Speed in the Western U.S.

There is growing interest in skillful wind forecasts beyond one week, as renewable energy source and electricity demand planning activities are directly impacted by weather conditions. CFAN has been making operational probabilistic forecasts of wind speed in the western U.S. using the ECMWF ensemble forecasts. Comparisons of the ECMWF forecasts calibrated against 20-year hindcasts and real time operational forecasts are presented, using a rank analog and pdf mapping technique. Forecast probabilities of exceedence for different wind thresholds of relevance to wind power generation are evaluated. Ensemble clustering of dominant weather regimes provides additional insights into the predictable components of the forecast. A forecast confidence assessment is made for each forecast based on identification of forecast ‘windows of opportunity’ determined from the current and predicted strength of teleconnections. Forecast evaluation statistics are presented as a function of region and circulation regime. An interactive web-based dashboard system displays the forecast information and real time prediction skill in a flexible and dynamic manner.