WMO Forecasts Weak La Niña Event: Potential Impacts on Global Weather

The World Meteorological Organization (WMO) has announced a 55% probability of a weak La Niña event occurring from December 2025 through February 2026, potentially influencing global weather patterns and necessitating proactive measures across various sectors.

La Niña is a climate phenomenon characterized by the cooling of sea surface temperatures in the central and eastern equatorial Pacific Ocean. This cooling influences global weather patterns, often leading to increased rainfall in some regions and droughts in others. La Niña is the counterpart to El Niño, which involves the warming of these oceanic regions. Both are phases of the El Niño-Southern Oscillation (ENSO) cycle, a significant driver of global climate variability.

As of mid-November 2025, oceanic and atmospheric indicators revealed borderline La Niña conditions. The WMO's forecast indicates a 55% probability of a weak La Niña event during the December 2025 to February 2026 period. Additionally, there is a 65% to 75% chance of neutral climate patterns developing between January and April 2026. The likelihood of an El Niño event during this period is considered low. (wmo.int)

While La Niña typically brings a temporary cooling effect on global average temperatures, the WMO emphasizes that many regions are still expected to experience warmer-than-normal conditions. This anomaly increases the risk of extreme weather events, such as floods and droughts, which can significantly impact agriculture and water resources. (wmo.int)

Historically, La Niña events have varied in strength and duration. For instance, a weak La Niña event that began in December 2024 was short-lived, ending by March 2025. Despite its brevity, it influenced global weather patterns, including increased Atlantic hurricane activity and dry conditions in parts of the United States. (apnews.com)

The anticipated weak La Niña could have several societal implications:

• Agriculture: Altered precipitation patterns may affect crop yields, potentially leading to food shortages or price fluctuations.
• Water Resources: Regions experiencing droughts may face water scarcity, impacting both agriculture and daily life.
• Disaster Preparedness: Increased likelihood of extreme weather events necessitates enhanced preparedness and response strategies to mitigate potential damages.

The WMO underscores the importance of accurate seasonal forecasts, stating that they can lead to substantial economic benefits and help save lives by enabling better preparation in sectors such as agriculture, energy, health, and transport. (wmo.int)

The WMO's forecast of a weak La Niña underscores the need for vigilance and proactive planning across sectors vulnerable to climate variability. By leveraging accurate seasonal forecasts, societies can better prepare for and mitigate the potential impacts of this climate phenomenon.