The Auckland region emergency management office is warning of forecast high swells and rough seas.
MetService says a storm is heading to New Zealand and it is expected to cover much of the country over the next few days.
The weather pattern may create heavy swells of up to seven metres on the West Coast between Friday evening and Saturday morning.
The Auckland region Civil Defence emergency management group is monitoring the situation and advising people to stay away from beaches.
It says boaties should consider whether their voyage should be delayed or canceled.
The Harbourmaster will close the Manukau Bar to vessels when the swell exceeds 4 metres.