Hurricane Florence continues to grow in strength and rose to a Category 4 storm, the National Hurricane Center (NHC) said Monday.

Florence has winds of 130 miles per hour (185 kilometers per hour) and is expected to increase in strength once it makes landfall along the U.S. East Coast later this week.

A Category 4 storm has winds of around 130 - 156 mph (209 - 261 kph) and is the second highest classification according to the Saffir-Simpson Hurricane Scale.

The NHC estimates the storm will first hit the southern coast of North Carolina on Thursday and continue north to Virginia by Saturday.

Evacuation orders have been issued for all counties along South Carolina’s coastline as well as the Outer Banks region of North Carolina, with winds expected to reach 150 mph.

As many as 1 million people could leave the coastal areas of South Carolina, the governor said Monday.

The governors of North Carolina, South Carolina and Virginia have all declared a states of emergencies.

"The bottom line is that there is increasing confidence that Florence will be a large and extremely dangerous hurricane, regardless of its exact intensity," the NHC said in a statement.

If Florence remains at Category 4, it would be one the strongest hurricane to make landfall on the continental U.S.

"If the latest NHC forecast comes to pass, #Florence will be the only hurricane on record to make a Cat 4 U.S. landfall so far north," Bob Henson, meteorologist at the Weather Underground, said on Twitter.

Hurricane watches were issued Tuesday for the coast lines of South Carolina, North Carolina, and Virginia by the NHC as life threatening flooding, damaging winds and heavy rainfall are expected.

Florence is one of three storms currently swirling in the Atlantic.

President Donald Trump encouraged residents in the path of the storms to take precautions and heed the orders officials. 

"To the incredible citizens of North Carolina, South Carolina and the entire East Coast - the storm looks very bad!" he said in a series of Twitter posts. "Please take all necessary precautions. We have already began mobilizing our assets to respond accordingly, and we are here for you!"