New Zealand braces for stormier summer as heat and humidity rise
Summer has arrived in New Zealand, bringing heat, humidity, and a surge in thunderstorm activity. Recent marine heatwaves have pushed sea surface temperatures higher, adding extra energy to the atmosphere and increasing the risk of heavy rain and storms.
Thunderstorms typically form when warm, moist air rises into cooler layers above. This process releases heat and separates electrical charges, leading to lightning. In New Zealand, these storms are often small—sometimes just a kilometre wide—and usually consist of single convective cells.
The combination of La Niña, rising sea temperatures, and a warming climate is making thunderstorms more likely. Forecasters expect these conditions to persist, with increased humidity and instability driving more active weather. The current La Niña may fade by the end of the season, but its effects on storm frequency and intensity remain a concern.
