Flood and gale warnings are in place across many coastal areas in the Pacific Northwest, whilst winter storm warnings remained for eastern parts of Maine, according to the National Weather Service.
"One final storm system will move across the Northwest today with heavy coastal rain and heavy mountain snow," it said.
Several alerts were affecting a number of major roads in Washington state, with "hazardous water conditions" closing a number of sections, the Washington State Department of Transportation said.
Some properties, roads and fields were seen deep in water in images and videos posted on social media and by local news outlets.
Around 2,600 flights to, from and within the United States were cancelled on Friday, according to Flightaware.com, with COVID-19 also affecting airlines.
More than 50,000 customers along the west coast are currently without power, while Virginia is the worst-hit state in east, data from poweroutage.us showed.
Earlier, a storm in the east left some parts of Kentucky, Virginia, Pennsylvania, New York and Maryland under 15 to 20cm of snow. Coastal New England was hardest hit as some towns saw more than 30cm of snow on Thursday and into Friday.
Federal government offices in Washington were closed, and dozens of school districts across the eastern half of the country canceled classes due to the snow and bitter cold.
The storm was the second this week to slam into the eastern United States. On Monday, the region was blanketed by up to 30cm of snow, stranding thousands of people for up to 27 hours when a nearly 80km stretch of Interstate 95 in northern Virginia became impassable.
