GENEVA

There is a 55% chance that a weak La Nina will influence global weather patterns over the next three months, the World Meteorological Organization (WMO) said on Thursday.

The agency said in an update that although La Nina has a temporary cooling effect on global average temperatures, many regions are still forecast to be warmer than normal.

La Nina is characterized by large-scale cooling of ocean surface temperatures in the central and eastern equatorial Pacific, combined with shifts in tropical atmospheric circulation, including changes in winds, pressure, and rainfall.

According to the WMO's Global Producing Centres for Seasonal Prediction, oceanic and atmospheric data indicated borderline La Nina conditions as of mid-November.

The probability of meeting full La Nina thresholds between December and February 2025–2026 stands at 55%, the update said. For January–March and February–April 2026, the likelihood of a return to ENSO-neutral (El Nino-Southern Oscillation-neutral) conditions increases to between 65% and 75%. There is little chance of an El Nino forming, the agency noted.

"Seasonal forecasts for El Niño and La Nina are essential planning tools for climate-sensitive sectors like agriculture, energy, health and transport. They are also a key component of WMO's contribution to support humanitarian operations," WMO Secretary-General Celeste Saulo said. "This climate intelligence helps us to avert millions of dollars in economic losses and to save countless lives."

National Meteorological and Hydrological Services will continue monitoring conditions to support decision-makers, WMO said.

Naturally occurring climate patterns such as La Nina are unfolding against a backdrop of human-induced climate change, which is driving long-term warming and intensifying extreme events.

The update projected above-normal temperatures across much of the Northern Hemisphere and large portions of the Southern Hemisphere from December to February, with rainfall patterns resembling those typical of a weak La Nina.