At least three people have been killed as the massive storm brings power outages, flood watches and flight delays to the US East Coast.
A woman died in flooding outside Charleston, South Carolina, and two men were killed in northeastern states as the storm moved toward Canada.
Millions of East Coast residents were under a flood watch and more than 700,000 were without power Monday.
Lasting through Tuesday, the storm is expected to pose a threat to holiday travel.
The weather has brought “widespread heavy rainfall, resulting in river flooding, widespread flooding, flash flooding and some areas experiencing road washouts,” the National Weather Service said.
The first storm-related death was confirmed in Mount Pleasant, South Carolina. Nancy Morrow, 72, was killed in the submerged vehicle, officials said. Officers jumped into the water and tried to save her.
Robert Harkey, 89, died Monday in Hanover, Massachusetts, after strong winds blew a tree onto his trailer, causing severe head trauma, local officials said.
A third person, who police have not yet identified, died in Windham, Maine. Authorities said he was trying to clear debris from his roof when a tree fell on him.
According to FlightAware, strong winds and rain created hazardous travel conditions, causing more than 3,400 delays and 500 flight cancellations. Airports in the Boston and New York areas were worst affected.
Schools across the New England region were also forced to cancel or delay classes due to road conditions.
The storm had several effects on several states along the East Coast:
In Boston, Massachusetts, local winds reached 50 mph (80 km/h), according to the National Weather Service.
Dozens of people in Georgetown, South Carolina, are in need of rescue after flooding near a waterfront area that received more than nine inches (22 cm) of rain, officials said.
In total, nearly 60 million people from Virginia to Maine were under a flood watch
The worst of the rain is expected to taper off Monday evening, but road conditions will still be treacherous, the National Weather Service said.
“Allow extra time for your commute and avoid driving through flooded roads,” the NWS said.
The storm is expected to move toward Canada late Monday, while the northeast could also see some snow Monday night.
The weather comes about a year after a major winter storm caused travel chaos in the U.S. during the busy holiday travel season.