Tonight's moon is bigger and brighter than any other full moon so far this year.

It's a supermoon that marks the start of a hat trick of bigger brighter full moons between now and the end of January.

The second is expected January 2. A super blue moon is expected on January 31 - being the second full moon in one calendar month.

A supermoon is called when the full moon coincides with perigee – the closest approach of the moon to earth in its orbit.

They usually happen less than a day apart, but this one is just outside the 24 hour day. Full moon was this morning Monday December 4 at 4.47 NZST, and perigee is tomorrow morning at 10.42am.

But it will still appear 14 per cent bigger and 30 per cent brighter tonight as the moon gets closer, by the minute.

At full moon earlier today it was 357,987km from the planet. At Perigee it will be 495km closer at 357,492km. It's about 50,000 closer than the full moon in June which was near apogee, the furthest distance.

The two full moons in January 2018 – on January 2 and 31 – also count as supermoons.

As is typically the case, the second of these three full moon supermoons just after New Year most closely coincides with lunar perigee, showcasing the closest and largest supermoon in this series.

The supermoon of January 31, which is probably a super blue moon, also coincides with a total lunar eclipse, which will be visible from New Zealand with the full eclipse beginning about 2am and ending after 3am.

MetService says most Kiwis will get a good view of the supermoon tonight. It'll be mainly fine in the North Island, with a few showers north of Tauranga and afternoon showers about the central high country.

The South Island's also set for fine weather, apart from cloudy periods and patchy light rain in the west and south.

Astrologer Richard Nolle, is credited with coining the term, supermoon as: … a new or full moon which occurs with the moon at or near (within 90 per cent of) its closest approach to Earth in a given orbit.

According to that definition, that means any new moon or full moon coming closer than 362,000 km of Earth in 2017 counts as a supermoon.