Arizona, Utah, and Nevada are under a flash flood watch with an additional three to six inches of rain possible from Los Angeles to Vegas.
Flooding from heavy rains destroyed at least four homes along the Beaver Dam Wash area Tuesday afternoon, the Tucson Citizen reported.
Utah officials have lifted an evacuation order for the town of Rockville after determining a dam on the Virgin River is not in danger of breaking.
Forecasters say the storm is moving east – bringing a white Christmas to places like Fargo, North Dakota and much of Minnesota.
Since Sunday, Utah's Wasatch Mountains received more than six feet snow with another two to four feet to come.
In Colorado, at least two to three feet of snow has fallen since Sunday and two to three feet more expected through Thursday.
ABC News' Mike Von Fremd, David Wright, Max Golembo and the Associated Press contributed to this report.