A northwesterly airflow lies over the country today, a cold front pushes onto the lower South Island this morning then slowly moving northwards reaching the lower North Island overnight. A west to southwesterly airflow lies over New Zealand on Wednesday, becoming unstable for the eastern South Island in the afternoon.

A mix of sun and cloud for the western North Island today, high cloud out east. A light shower or two may affect Kapiti, rain moves into the southwestern North Island overnight. Heavy rain about South Westland spreads into North Westland during the afternoon, easing later in the evening, thunderstorms are possible about South Westland in the morning. Dry to start about Southland and Otago, showers develop in the afternoon possibly heavy with thunderstorms for coastal Otago. Canterbury and Marlborough have a mainly sunny day with some high cloud.

A few patchy showers for the western North Island on Wednesday, clearing in the evening for most although the odd one may hang about Northland till overnight. Mainly dry in the east with some high cloud, late afternoon or evening southerlies may bring some lower level cloud and the risk of a shower. Occasional showers for the West Coast of the South Island, clearing evening. The odd shower for the south and east of the South Island, showers may become heavy with hail / thunder in the afternoon then easing evening. Unstable activity mainly Otago Peninsula northwards through into North Canterbury.

By Weather Analyst Aaron Wilkinson – WeatherWatch.co.nz