A powerful Category 4 hurricane is churning toward the Gulf Coast, prompting mandatory evacuations across coastal communities in Louisiana and Mississippi.

Hurricane Marco, packing sustained winds of 145 mph, is expected to make landfall near the Louisiana-Mississippi border sometime Thursday evening, according to the National Hurricane Center.

Governor Edwards declared a state of emergency Tuesday and activated the National Guard to assist with evacuation and emergency response operations.

The storm is expected to bring a dangerous storm surge of 12 to 16 feet along with torrential rainfall that could produce inland flooding.

Emergency management officials urged residents in evacuation zones to leave immediately and seek shelter in designated facilities inland.