US weather officials are warning people of a "life-threatening storm surge" as Hurricane Dorian approaches the state of Florida.

The US National Hurricane Center says Dorian was off the coast of Florida as of 10 p.m., local time, on Tuesday and moving northwest at 9.6 kilometers per hour.

The storm is rated a Category 2 on a five level scale and expected to move north along the US east coast from Tuesday through Friday.

The officials say Dorian is packing winds of up to 177 kilometers per hour, with an atmospheric pressure of 958 hectopascals at its center.

The weather officials say Dorian may bring more than 300 millimeters of rain over the weekend and cause waves of more than 2 meters.

State officials from Florida, Georgia and South Carolina have issued evacuation orders for more than 1 million people, as they may face life-threatening floods.

Extra caution is being taken as last year 30 people died in multiple hurricanes in Florida and other states.

NHK