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The weak La Ni帽a event that emerged in December 2024 is likely to be short-lived, according to the latest World Meteorological Organization (WMO) update.

Forecasts from the WMO Global Producing Centers for Seasonal Prediction indicate that the current cooler than average sea surface temperatures in the equatorial Pacific are expected to return to normal. There is a 60% probability that conditions will shift back to ENSO-neutral conditions (neither El Ni帽o nor La Ni帽a) during March鈥揗ay 2025, increasing to 70% for April鈥揓une 2025.

Meanwhile, the probability of El Ni帽o developing is negligible during the forecast period (March to June). However, uncertainty in the long-lead forecasts is higher than usual due to the boreal spring predictability barrier, a well-known challenge in long-term forecasts of El Ni帽o and La Ni帽a.

"Seasonal forecasts for El Ni帽o and La Ni帽a and the associated impacts on weather and climate patterns globally are an important tool to inform early warnings and early action and are one of a wide suite of services offered by the WMO community to support decision-making," said WMO Secretary-General Celeste Saulo.

"These forecasts translate into millions of dollars worth in economic savings for key sectors like agriculture, energy and transport, and saved thousands of lives over the years by enabling disaster risk preparedness," she said.

La Ni帽a refers to the large-scale cooling of the ocean surface temperatures in the central and eastern equatorial Pacific Ocean, coupled with changes in the tropical atmospheric circulation, including changes in winds, pressure and rainfall patterns. Typically, La Ni帽a brings climate impacts that are the opposite of El Ni帽o, especially in tropical regions.

However, the impacts of naturally occurring climate events such as La Ni帽a and El Ni帽o on climate patterns are taking place in the broader context of human-induced climate change, which is increasing global temperatures, exacerbating extreme weather and climate, and impacting seasonal rainfall and temperature patterns.

Thus, January 2025 was the despite weak La Ni帽a conditions being present since December 2024, when observed sea surface temperature anomalies in the equatorial Pacific crossed the La Ni帽a threshold.

While the El Ni帽o-Southern Oscillation (ENSO) is a key driver of global climate patterns, it is not the only factor shaping the Earth's climate. To provide a more comprehensive climate outlook, WMO also issues regular Global Seasonal Climate Updates (GSCU). These updates take into account the influence of key climate variability patterns, including the North Atlantic Oscillation, the Arctic Oscillation and the Indian Ocean Dipole.

The updates also monitor the status of North Tropical Atlantic (NTA) and South Tropical Atlantic (STA) Sea Surface Temperature index anomalies, as well as the global and regional anomalies of surface temperature and precipitation and their evolution over the upcoming season.

With above-normal sea surface temperatures expected to persist across all major oceans鈥攅xcept for the near-equatorial eastern Pacific鈥攖he latest GSCU forecasts above-average temperatures over nearly all land areas worldwide.