American forecasters in Taufuna have issued a gale watch warning for American Samoa.
A tropical depression was located about 160 kilometres southeast of Manu'a at 6am local time this morning.
It was intensifying rapidly and is moving southwest at about 16 kilometres an hour.
Winds are expected of up to 56 kilometres per hour by this afternoon and surf of up to 12 feet is expected to pummel the shores of Tutuila and Manu'a.
The National Weather Service has advised residents to take necessary precautions to protect life and property.