Incorporating MJO and ENSO information into probabilistic temperature forecasts over North America

Previous work has shown that the combined influence of the El Niño-Southern Oscillation (ENSO) and Madden-Julian Oscillation (MJO) significantly impacts the wintertime geopotential height field over North America for lead times of up to four weeks, which offers the promise of enhanced probabilistic forecasts in the forecast period from weeks 2-4. Here we evaluate probabilistic temperature forecasts over North America derived solely from historical MJO and ENSO relationships with temperature. This evaluation demonstrates that there are, in fact, particular states of the MJO and ENSO that allow skillful temperature forecasts over parts of North America beyond week two. Next we demonstrate a framework for combining these statistical relationships of the MJO and ENSO influence on temperature with dynamical model forecasts from the CFS version 2, which further refines the probabilistic temperature forecasts in weeks 2-4. This framework shall serve as a prototype for a multi-model ensemble forecast system that combines the expected influence of ENSO and the MJO with performance information from several dynamical forecast models.