Strong storms were expected to persist over the West Coast on Thursday as another trough of low pressure pushed onshore.
A third wave of energy in the storm was forecast to move over central California and pull in more moisture, allowing for another day of scattered showers. Periods of heavy precipitation was expected in northern California, including snowfall over the Sierra Nevadas.
Some thunderstorms could turn severe. Strong winds with gusts up to 50 mph were expected, along with up to 2 inches of rain. In the Sierras, elevations above 5,000 feet could see up to 6 inches of new snow.
The storm was forecast to take a more southern route, meaning more rain and thunderstorms could hit southern California rather than the Pacific Northwest. The north was expected to see overcast skies with a few light showers and another 2 to 4 inches of snow in the Cascades.
Wet weather was expected to persist in the South as a low pressure system moved from the Southern Plains, over the Mississippi River Valley and up the Tennessee and Ohio Valleys. Flow around the system was forecast to push warm air in from the south and create a moist warm front that could kick up scattered showers.
The northern areas of the system could see periods of frozen rain and sleet, with light snow in the Upper Midwest. Rain was expected to extend down the Mississippi, though thunderstorms could be contained to the Gulf states due to abundant energy and moisture available from the Gulf of Mexico.
On Wednesday, temperatures in the Lower 48 states ranged from a low of minus 9 degrees at Raco, Mich., to a high of 87 degrees at McAllen, Texas.