On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.

Chance of above normal rainfall patterns for El Niño and La Niña in New Zealand

El Niño and La Niña impact seasonal rainfall patterns across Aotearoa/New Zealand. These maps show the probabilities of above normal rainfall (>100% of normal) during historical El Niño and La Niña events. Here’s an example on how to interpret the maps: during El Niño summers, Northland and Auckland have a low chance (<20%, coloured red), of experiencing above normal rainfall.