A big low pressure system moves out of the Tasman Sea today with its centre passing over central New Zealand later in the afternoon / evening. This low will usher in southerlies over the South Island and a northwest airflow for the North Island. A cool southerly airflow lies over New Zealand on Tuesday, the place to be is the West Coast of the South Island with a mostly sunny day in store.

A wet day for most of the North Island today, heavy rain is looking likely for southern parts of the Island then easing later on today or overnight. Thunderstorms may also feature about Taranaki for a time. For the South Island, rain develops this afternoon about Nelson and Marlborough (possibly heavy). Mostly cloudy skies along the east coast, any early spots of rain clear in the west then expect areas of cloud and some sun. Late afternoon or evening patchy rain / drizzle moves onto the east coast.

Showers ease for most areas on Tuesday, showers pick up again from afternoon about Southland however, moving into Otago in the evening. Northland also sees showers push in during the evening.

By Weather Analyst Aaron Wilkinson – WeatherWatch.co.nz