Overview
The North American Multi-Model Ensemble (NMME)—led by NOAA in partnership with DOE, NSF, NASA, and U.S. and Canadian research institutions—is an experimental climate forecasting system that combines a suite of different models. Using a combined system of models, each with different individual strengths in predicting phenomena, can enhance the overall success of a prediction beyond what would be possible with a single model.

The following link provides additional information:
cpc.ncep.noaa.gov/products/NMME/

Research and Societally Relevant Outcomes
Although NMME was developed as a research experiment, NOAA has successfully used the system to inform climate predictions. An operational version of NMME—where “operational” refers to use of the system as part of the national climate prediction capacity—is under development and shows promise. For example, model forecasts initialized in November 2011 were able to effectively predict temperatures for March 2012—four months later. NMME is thus expected to improve our ability to forecast climate conditions anywhere from months to seasons in advance.