A cold south to southwesterly airflow over the South Island spreads over the North Island on Tuesday.

Showers, becoming heavy with a risk of thunderstorms and hail in the afternoon for the upper North Island as southwesterlies freshen. Conditions ease later in the evening. Rain develops about Wellington and Wairarapa in the morning then spreading northwards into Hawkes Bay and Gisborne in the afternoon. Snow lowers about the Central Plateau overnight to 600m.

Rain or showers about the upper South Island eases during the day, gradually clearing from the south. Morning snow to 300m about Canterbury then clearing, 500m for Marlborough; gradually lifting and clearing. Fairly dry about the lower South Island but the odd shower may pester Southland, mainly in the morning.

By Weather Analyst Aaron Wilkinson – WeatherWatch.co.nz