Isaias is traveling up the East Coast after leaving flooding and fires

People walk on the flooded Sea Mountain highway in North Myrtle Beach, South Carolina, late Monday night. Jason Lee/The Sun News/AP

After pummeling the Carolinas, Isaias is forecast to gradually weaken as it brings strong winds Tuesday all along the East Coast, including in Washington DC, Philadelphia and New York.

The storm is expected to lash Philadelphia with winds of up to 65 mph, while New York will get pounded with winds of 65 to 70 mph.

Isaias hurled sustained winds of 85 mph and became a Category 1 hurricane before reaching land around 11:10 p.m. ET near Ocean Isle Beach, North Carolina, the National Hurricane Center said.

It was downgraded to a tropical storm Tuesday morning, with maximum sustained winds down to 70 mph. But that doesn't mean the danger is over.

Howling wind and water washing across in "one to two foot swells" closed a bridge Monday night in Sunset Beach, North Carolina, the Sunset Beach Police said on Facebook. Streets in Holden Beach became rivers as water quickly rose, Jessi Viox told CNN.

"Getting ready for Round 2," Viox said. "The eye has moved around us, and now here comes the back end."

Brunswick County, North Carolina, reported "numerous calls" for water rescues, structural fires, structural collapses and people trapped in flooding houses," Oak Island Water Rescue said on Facebook.

Before Isaias even made landfall, the top of the Apache Pier Pavilion was seen lifting off in the wind.

And multiple structures in Ocean Isle Beach were reported to be ablaze, according to the Horry County Fire Rescue in South Carolina.

Tropical Storm Isaias was over Virginia in the National Hurricane Center's 8 a.m. ET advisory. It's forecast to travel northward today.

Millions are under tropical storm warnings, including people in Washington, New York City and Boston

New York City could see wind gusts of 60 to 70mph this afternoon — likely the highest since Super Storm Sandy

Here's a look at the latest forecast from the National Hurricane Center:

Workers erect temporary flood barriers in the South Street Seaport neighborhood in preparation for potential flooding and a storm surge from Tropical Storm Isaias on August 3 in New York. Spencer Platt/Getty Images

A tornado watch has been issued for several major Northeast metros, including New York City and Philadelphia, until 4 p.m. ET. The watch includes parts of Connecticut, New Jersey, New York and Pennsylvania.

The bands of Tropical Storm Isaias will contain embedded strong thunderstorms that can quickly produce tornadoes.

Many tornado warnings have been issued as well, though tornadoes in landfalling tropical systems often spin up so fast they come with little or no warning.

There is also a tornado watch in effect until noon for Delaware, Eastern Maryland and Coastal Virginia, which has already seen multiple tornadoes reported this morning.

In total, more than 30 million people are under tornado watches at this time.

North Carolina Gov. Roy Cooper leaves the podium after a press conference about the state's preparations for then-Tropical Storm Isaias on Sunday, August 2, in Raleigh. Ethan Hyman/The News & Observer/AP

Hurricane Isaias has claimed the life of at least one person in North Carolina, Gov. Roy Cooper said during an interview with Good Morning America on Tuesday. 

It is unclear where in the state the fatality occurred. 

Cooper says the storm slammed onto the shore just after 11 p.m. ET on Monday causing widespread damage in the southeastern part of the state. 

Cooper says approximately 355,000 people remain with out power.