New Zealand climate patterns
A forecast covers the next week. These pages cover the patterns behind it — the Pacific shifts that make one summer drier than the last, read off the published record rather than described in general terms.
El Niño
The warm phase: what it is, how strength is measured, what past events did around the world, and the regional pattern it tends to bring New Zealand. Carries the current Pacific figures from NOAA.
La Niña
The cool phase: north-easterly winds, a wetter and more humid north-east, and the 2020–23 event behind the Auckland Anniversary floods and Cyclone Gabrielle.
El Niño vs La Niña
The two side by side — what causes each, how often they occur, how quickly the Pacific switches between them, and which one it is in right now.