A storm system drifting northeastward through mid-week will stall over the Great Lakes region.  As the storm begins to weaken, the twin threat of wintry weather (from the northern Plains into the upper Midwest) and severe thunderstorms (mostly across the Southeast) will slowly subside.  Concurrently, another major Pacific storm system will approach the West Coast, delivering additional flooding rain in parts of California on January 4-5, but further boosting high-elevation snowpack.  Other areas of the West will hydrologically benefit from the sprawling storm, which could deliver 5 to 10 inches of precipitation in portions of northern and central California. 

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