We thank Harold Brooks, Charles Doswell, Brian Mapes, Gregory Carbin, Kerry Cook, and anonymous reviewers for their thoughtful comments and suggestions. This study was motivated and benefited from interactions with scientists at NOAA NSSL, ESRL, GFDL, CPC, NCDC, and AOML. In particular, we wish to thank Wayne Higgins, Tom Karl, and Marty Hoerling for initiating and leading discussions that motivated this study. This work was supported by grants from the National Oceanic and Atmospheric Administration’s Climate Program Office and by grants from the National Science Foundation.
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