The severe weather is associated with an active convergence.
The latest weather bulletin warns of heavy downpours with poor visibility, strong gusty winds, foggy and slippery roads over mountain passes and ranges.
Motorists can expect pooling near roadsides and waterways.
Rivers will likely overflow and there could be landslides.
Strong currents as well as very rough seas with wind waves and swells increasing up to 2.5-3 metres are expected in marine waters.
Photo supplied Samoa Met Division