As a mountainous island chain, New Zealand has a complex maritime climate whose weather is greatly affected by the mountains and the sea. The climate ranges from warm sub-tropical in the north, to cool sub-temperate in the south. The prevailing winds are westerly and this leads to a reasonably high rainfall particularly in the west. New Zealand's location relative to Antarctica means that weather systems from that direction can cause very sudden deterioration in weather and extreme drops in temperature particularly in the south.
