Forecasters and Earth Sciences New Zealand scientists expect a significant El Niño event to bring dry winter weather to much of New Zealand [1, 2].

This shift in climate patterns could disrupt water availability and agricultural productivity across the country. Because the phenomenon alters rainfall distribution, different regions will face opposing weather extremes during the 2026 winter season [1, 3].

Scientists said the El Niño effect occurs when surface water in the eastern Pacific becomes hotter than usual [1]. This temperature shift moves tropical rainfall eastward, which subsequently reduces the amount of rain that reaches New Zealand [1].

The impact will not be uniform across the islands. Forecasters said drier conditions will dominate the northern and eastern regions of the country [2, 3]. Conversely, the western regions may experience wetter conditions and increased rain [2, 3].

Monitoring continues as the event develops. Experts said there is a 60% chance [4] that the El Niño will be strong by the following spring [4].

Local authorities and scientists continue to track the Pacific surface temperatures to refine these projections. The current data suggests a significant event that will likely shape the seasonal outlook for the majority of the population [1, 2].

“A significant El Niño event is expected to bring reduced rainfall to much of New Zealand this winter.”

The predicted divergence in rainfall—dry in the east and north, wet in the west—creates a dual challenge for New Zealand's infrastructure. While eastern regions may face drought-related water shortages, western regions must prepare for potential flooding and runoff, complicating national emergency management for the 2026 winter.