Plan ahead for El Nino

What is El Niño?

El Niño and La Niña are natural climate patterns in the Pacific Ocean that influence weather patterns across New Zealand. These cycles occur every 2–7 years and are a key driver of seasonal climate variability in New Zealand.

El Niño is characterised by warmer sea surface temperatures in the central and eastern Pacific. This leads to stronger and more frequent westerly winds over New Zealand and typically results in drier conditions in eastern regions and increased rainfall in the west, with more wind and temperature variability overall.

La Niña is characterised by cooler sea surface temperatures in the central/eastern Pacific, which leads to more northeasterly airflow over New Zealand and typically brings more warmer, humid conditions with higher rainfall in northern and eastern areas.

Outlook

New Zealand will enter an El Niño phase in winter 2026, with forecast predictions indicating that it is likely to persist through the coming winter, increasing in intensity through spring and summer, before weakening into autumn 2027.

El Niño events typically last 9 - 12 months, but the strength can vary over time. Current climate models (e.g. NIWA and international agencies) suggest a moderate to strong event, although there remains uncertainty around how conditions may evolve later in the season.

What could this mean for your region?

Conditions are not the same everywhere. A useful starting point is to think about the broad pattern, then apply it to your own farm's soils, water access, stocking policy and pasture growth and reliability .

Upper North Island (Northland, Waikato, Bay of Plenty):

Rainfall may be more variable and unreliable.
Warm conditions may persist, increasing evapotranspiration.

Lower North Island (Taranaki, Manawatū, Wairarapa):

Western areas may see near-normal rainfall.
Eastern areas tend to become drier.

Upper South Island (Tasman, Marlborough, Nelson):

Dry conditions likely, particularly in Marlborough.
Increased wind exposure.

West Coast and Southland:

Possibility of increased rainfall and wind.
Likelihood of greater weather variability.

East Coast South Island (Canterbury, Otago):

Typically, drier than normal associated with strong north-westerly winds.
Increased risk of drought.
Increased irrigation demand.

How to prepare on farm

Plan early and update often

Uncertainty is a key feature of El Niño. Regularly review weather forecasts and seasonal outlooks.

Use reliable weather forecasting tools like NIWA FarmMet and MetService text alerts
Update plans as conditions change, particularly through spring and summer
Use scenario planning (best case / expected / worst case)

Manage feed supply and demand

Impacts on pasture growth may require adjustments to maintain feed supply.

Update feed budgets early and frequently
Be aware of the potential for feed deficits, especially in late spring and summer
Secure or identify supplementary feed options ahead of time
Adjust rotation speed and grazing management to protect pasture recovery

Make timely stocking decisions

Where possible, more closely align stock numbers with expected feed supply.

Review stocking rate where deficits are likely
Consider strategic culling where practicable
Prioritise feeding of highest-producing or most at-risk animals

Protect pasture and farm resilience[

Maintaining pasture condition is critical for both current and future productivity. Feed budgets and feed allocation calculators can help you model supply and demand, identify pinch points early, and compare response options.

Avoid overgrazing and maintain appropriate grazing residuals
Protect pasture persistence, particularly during dry hot periods and periods of soil moisture deficit
Take opportunities to conserve surplus feed if conditions allow early in the season
In wetter situations, ensure you have options to protect pasture and soils from pugging and damage

Manage animal health and welfare

Extreme conditions can impact both animals and people.

Monitor for livestock heat stress, especially during hot, dry, and windy conditions
Where possible, ensure livestock have access to shade and holding in confined areas and on concrete is minimised
Be aware and attentive of the increased risk of lameness and metabolic stress in wetter areas and/or where wet conditions are prolonged. Discuss with your vet any options to manage these risks

Review financial position

Reduced production combined with the potential for increased imported feed costs can place pressure on operating margin.

Use existing budgeting and planning resources to assess the impact of different scenarios on cashflow and profitability
Identify where costs can be managed without compromising long-term farm performance
Seek advice from your bank, accountant or other trusted financial advisors