The first day of spring has dawned - and it's causing more havoc at Auckland Airport.

The Airport's website shows 26 domestic departure flights have been cancelled and 15 arrivals as fog rolls in this morning.

It is the third day in a row that fog has affected Auckland and caused flights to be cancelled or delayed.

While it may take until late morning for the fog to burn away, much of the country can expect a clear, sunny day after that, according to Metservice meteorologist Andrew James.

At the moment, though, there is "low visibility" around affected areas, mainly in Auckland and Waikato.

Eastern Bay of Plenty and parts of Taranaki may find the fog creeping that direction as well. Light winds and clear skies overnight have helped the temperature drop and allowed "that low level mist".

Today's temperatures will be typical for this time of year, reaching mid to high teens in the north, and mid to low teens in the south, James said.

Auckland should get a high of 17C and a low of 11, while Wellington may reach 14C today and 10C overnight. Christchurch should also reach 14C today, with a low of 4C overnight.

Once the sun is out, James recommended people use today to get their outside chores down, as the rest of the weekend won't be as nice.

A front coming through overnight will bring showers to western areas late this evening.

"[There's a] bit of a deteriorating trend."

The North Island will be showery, and the South Island can expect heavy rain in some places on Sunday.