Northeast winds could approach severe gales in exposed places, according to MetService.
Meanwhile, periods of heavy rain with thunderstorms and localised downpours are possible.
Top Energy has reported an outage near Fairburn in the Far North, which has impacted 151 customers on several roads.
The cause was under investigation as of 2pm.
The watches came as the New Zealand Institute for Earth Science [formed by the newly merged GNS Science and Niwa] revealed the second half of 2025 is likely to experience a wet start.
The institute’s seasonal climate outlook for July to September predicts warmer-than-average temperatures for the second half of the year.
Northland has a 60% likelihood of above-average temperatures and a 45% chance of above-normal rainfall from July to September, according to the Earth Science outlook.
Principal scientist and meteorologist Chris Brandolino said there was a high likelihood that tropical and subtropical influences and low-pressure systems could affect New Zealand over the next three months.
“Rainfall is expected to be above normal in the north of both islands, and near normal or above normal elsewhere, except for the West Coast of the South Island, where drier than usual conditions are possible.”
Above-average rainfall and heavy rain events could lead to an increased chance of flooding.
Cold snaps were expected to be less frequent than usual, Brandolino said.
Brodie Stone covers crime and emergency for the Northern Advocate. She has spent most of her life in Whangārei and is passionate about delving into issues that matter to Northlanders and beyond.