Tropical Cyclone Wilma is expected to pass American Samoa's main island, Tutuila, within the next hours.
The category-1 storm has sustained winds of up to 110 Kilometres an hour, with gusts in excess of 130 kilometre an hour.
The Governor Togiola Tulafono activated the Emergency Operations Center about six hours ago.
This means that all government agencies have to report to the centre.
A marine warning says there is a hazardous surf up to five metres throughout the storm, causing some flooding.
Emergency responders evacuated Masausi village last night as waves were coming in further to the village.
As the cyclone passes in a southerly direction, it will also affect Samoa's main island, Upolu.
A cyclone alert has now been issued for Fiji's eastern islands.
An alert is also in place for Tonga's northern islands.
And for Tokelau, an alert is still in force but winds there are now expected to ease.