"The swells will remain around the 4m mark, but as we get into the weekend it will drop to 2m."
On Wednesday, swells at Napier Port were at 2m, with swells of up to 3.5m in deeper water.
After two young boys were spotted in heavy surf on Napier's Maine Parade on Tuesday, Coastguard Hawke's Bay skipper Henry van Tuel urged the public to remain vigilant near the water.
"Having personally been involved in two rescues along Marine Parade - one successful and one unsuccessful – I'm all too aware of the dangers of Marine Parade, especially when the surf is running," he said.
Ferris said as we approach the weekend, the weather will clear up before getting worse.
He said after being caught up in an eastern regime with plenty of cloud and wet weather, it'll change to a westerly regime over the weekend.
On Friday, Napier and Hastings will see highs of 16C and 15C respectively, with high clouds and brief showers expected in the early evening.
"It's not until the second half of Saturday that the main front passes over, with some breezy northerly winds and some wet weather expected," Ferris said.
Highs of 17C are expected on Sunday in both Napier and Hastings, with overnight lows of 7C and 6C respectively.