Lasting through the middle of the week, another powerful Pacific storm system will batter northern and central California and the western Great Basin with flooding, high-elevation snow, and potentially damaging winds.  Rain and melting snow could lead to additional pressure on levees and dams.  Meanwhile, cooler air settling into the South could result in frost and sub-freezing temperatures on Tuesday and Wednesday mornings as far south as central sections of Mississippi, Alabama, and Georgia, as well as portions of the Carolinas. 

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