Severe gale or north-east winds are possible over Northland tonight and tomorrow.
The MetService will be updating its weather warnings this morning, he said.
"We might add new areas in. The anti-cyclone that has brought us a sustained period of fine weather is moving away to the east and we're now having a front across the country," Mr Brenstrum said.
"During tomorrow, we will end up with rain in many parts of the country, though [it will] probably stay dry in South Canterbury and perhaps parts of Otago.
"And after that, it's more action with westerlies and there'll be more fronts coming, so that continues to bring rain to the western part of New Zealand; probably through to Sunday.
"Some places won't get much rain, because most of what's coming is coming from the west or north-west."
Rain will develop this morning in Kaitaia, where strong north-east winds are also forecast.
A high of 18C is expected there, the same in Whangarei, which is in for a cloudy day and rain this evening.
Aucklanders are in for a fine but cloudy day. However, there is a chance of drizzle, an overnight low of 15C and expected high of 18C.
Similar conditions are expected in Hamilton, Tokoroa and the Waikato, as well as New Plymouth, Napier and Masterton; which are all set to be fine, save for some cloud.
Palmerston North and Wellington are in for mainly fine weather today, and temperature highs of 16C and 15C, respectively.
Those in Tauranga will need an umbrella. "Occasional drizzle" is forecast and a high of 18C.
Despite the severe weather warnings in place for some areas tonight, mainly fine weather is expected over the South Island throughout the day.
Blenheim is mostly sunny with morning frosts and a high of 16C, and Greymouth is fine but a little cloudy.
Those in Christchurch will see nothing but sunshine today, although chilly conditions -- a high of 14C and an overnight low of 2C -- will mean people will have to wrap up.
Dunedin is also in for a whole lot of sun, with a high of 12C, and Queenstown and Invercargill will also both be fine but with morning frost and fog and a temperature high of 11C and 10C respectively.