Swells of up to two metres high are set to hammer Hawke's Bay shores on Sunday and Monday.
Niwa Meteorologist Ben Noll said a "tropical disturbance" currently hovering above Tonga is set to pass by the east coast of New Zealand on Sunday with swells peaking by Monday morning.
Luckily the Mega Fish competition wraps up on Saturday as swells could reach up to 1.6-2m with Noll advising those who were out on boats on Sunday to take care.
"On Sunday afternoon through to Monday afternoon the weather seems to come with some enhanced wave and swell action," Noll said.
"It's not a cyclone, but a tropical disturbance which will drop down south from Tonga towards the east of New Zealand.
"It will be pretty far offshore, well east of the mainland, but given the track it will increase the winds from the north-east and you'll start to see noticeably higher seas on Monday."
The large swells are not likely to linger with large wave action set to cease by late Monday.
"It will increase during the day on Sunday and will peak sometime early Monday then you'll see it pull back later that day."
Noll recommended that people take care on Hawke's Bay beaches whether they were surfing or out in boats.
"Just don't put yourself in a position where you could be in any danger. Take all the right precautions and be sensible."
Hawke's Bay is prone to large swells at this time of year, particularly on Marine Parade.
On January 31, 1994, a 58-year-old Danish woman was swept out to sea during a morning stroll and rescued by passing by surf life saver.
On March 3, 1994, a 17-year-old girl was also swept out to sea during a late-night stroll, but was also rescued.
Large swells caused by strong gales in June last year flung two 3.8 tonne shipping containers into the sea at Napier Port.
One was washed up on Westshore beach along with a navigational buoy which broke from its moorings in extreme swells which reached up to 8.5m.
The second container was never recovered with a port spokesperson saying that it was most likely punctured by rocks when falling into the water and would be resting on the ocean floor.