On Thursday, significant rain will develop in portions of the western Gulf Coast region, later expanding to encompass other areas in the South, East, and lower Midwest. Most of the precipitation (locally 1 to 3 inches or more across the South) will end by New Year’s Day, except in the Northeast.
Meanwhile, a series of Pacific disturbances will maintain unsettled, showery conditions across the western U.S. In fact, 5-day precipitation totals could reach 5 to 10 inches or more in northern and central California, including key watershed areas in the Sierra Nevada.