Multiple states of emergency have been declared across the US east coast as Hurricane Florence heads towards the region.

The most powerful storm to threaten the Carolinas in 30 years is expected to make landfall as a category four hurricane on Friday morning packing 140 mph winds.

The governors of North Carolina, South Carolina, Virginia, and Maryland and the mayor of the District of Columbia – Washington DC – have declared states of emergency.

North Carolina, South Carolina, and Virginia have issued mandatory evacuation orders for coastal areas.

“Conditions in affected states are likely to include widespread flash flooding, storm surge in coastal areas, and strong winds capable of damaging property and infrastructure,” the Foreign and Commonwealth Office warned in an updated travel advisory.

“Hurricane Florence is forecast to bring life-threatening weather conditions to North Carolina, South Carolina, and Virginia, with potential effects in Maryland, the District of Columbia, and eastern Georgia.

“Those in affected areas should monitor local and national media for updates.”

The FCO added: “If you have planned travel to the region before 15 September, you should keep your plans under close review and be prepared to amend or postpone them. Keep in contact with your tour operator or transport/accommodation provider as appropriate.”

American Airlines is monitoring three separate hurricanes which may impact its operations this week.

The carrier said: “Hurricane Florence aims to make landfall on the east coast, while Hurricane Olivia is heading toward Hawaii and Hurricane Isaac is tracking toward the Lesser Antilles.

“Our thoughts are with those who are in the path of these potentially damaging hurricanes.

“We are in regular communication with our national partner, the American Red Cross, which has the unique ability to activate immediately and assess critical needs following disaster.

“We stand ready to activate our disaster response giving platform soon, where our customers and team members can assist those in need.”

United Airlines warned that Hurricane Florence is predicted to make landfall in the southern part of North Carolina and cause extensive damage that will impact communities throughout the region.

“In preparation, United has plans underway to ensure our customers, employees and facilities are safe,” the carrier said.

“United’s customer service teams are proactively reaching out to customers with reservations during the forecasted impact time and rebooking them on alternate flights.”

Meanwhile, Typhoon Mangkhut is forecast to bring hazardous sea and weather conditions to Hong Kong and Macao from Sunday.

“You should monitor the progress of approaching storms and follow the advice of local authorities,” the FCO said.