The state news agency ONA reported that power would be cut in the coastal districts after evacuation is complete. Work was cancelled and medical facilities were ordered to close.
The cyclone is expected to come ashore between 6 p.m. and 9 p.m. local time (14:00-17:00 GMT). High winds and storm surge were reported onshore in the afternoon.
Shelters have opened throughout the sultanate. ONA said more than 600 people had arrived at 10 relief centers in Al Batinah North Governorate, north of Muscat.