We are grateful to Matt Wheeler, Eric DeWeaver, John Molinari, Dave Lorenz, and Dan Vimont for their helpful input, and Kerry Emanuel and two anonymous reviewers for their thoughtful reviews of the original manuscript. This work was funded by the Risk Prediction Initiative of the Bermuda Institute of Ocean Sciences and by NOAA’s National Climatic Data Center. SJC acknowledges support from NOAA Grant NA08OAR4320912. The NOAA ERSST V3 data and NCEP–NCAR reanalysis data, and the AMM, Niño 1 + 2, and NAO indices were provided by the NOAA/ESRL Physical Sciences Division, Boulder, Colorado, from their Web site at http://www.esrl.noaa.gov/psd/. The MJO index was obtained from the Center for Australian Weather and Climate Research.
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