The National Hurricane Center downgraded Hilary to a post-tropical storm on Monday, but the system still poses a significant rainfall and flooding threat to the parched desert Southwest, and regions further north.
Heavy rain in local areas and isolated flooding are possible in the Intermountain West, according to forecasters.
In Nevada, the National Weather Service warned of widespread rain and potential flash flooding through Tuesday. Flash flood watches were in place for north central California and western Nevada through Monday evening.
Some flooding may be possible as far north as Oregon and Idaho.
Flooding knocked out power and isolated the community of Mount Charleston in Nevada, about 40 miles west of Las Vegas, after it washed out an access road.
Republican Gov. Joe Lombardo declared a disaster on Sunday, and the National Guard deployed to the area.
Hilary made landfall in Baja California in Mexico and was the first tropical storm to affect the state of California for 84 years. The storm brought heavy rainfall, flooding, and mud and debris flows that blocked roads.
In some places, the storm delivered six months' worth of average rainfall in the space of hours. It set a new record for the heaviest rainfall in San Diego.
Officials in California say there have been no reported deaths or serious injuries as a result of the storm.
