The storm was "starting to bring one of the most dramatic weather days in recent memory," the National Weather Service said. California's governor declared an emergency in eight counties.
The National Weather Service warns the storm could drop unprecedented rain over a wide area from Saturday night through early next week, with the period of most concern from Sunday into early Monday.
There is a simple reason for male groundhogs to seize the Feb. 2 holiday. But the handlers of female groundhogs say their animals are more accurate than Punxsutawney Phil.
Three big storms in a month devastated communities inland and along the coast. Now residents in vulnerable areas are considering how to deal with the threat of rising water.
Scientists looked at trees to better understand the interplay between temperatures and droughts in the Western U.S. Human-caused climate change is exacerbating both.
Last week, it was so cold in Beaumont, Texas — with lows of 18 degrees Fahrenheit — that alligators across the area were found frozen underwater, while still breathing.
Record rain has caused flooding in San Diego County that blocked roads, damaged homes, and prompted rescues. The mayor of San Diego has declared a state of emergency.