Recent intense rainfall in the South Island is due to atmospheric rivers (ARs) siphoning warm, moist air from the tropics. Atmospheric rivers are a key feature of Aotearoa/New Zealand’s climate, and as climate change effects intensify, events like these may become worse. Mike Stone (Pākehā) explains what we know about ARs in Aotearoa/New Zealand, and Mere Manning (Kahungunu ki te Wairoa) looks at tohu predicting weather.