UN Lowers Likelihood of La Niña in 2024

The United Nations announced on Wednesday that the chances of the cooling La Niña weather phenomenon developing this year have slightly decreased since June.

According to the latest update from the UN's World Meteorological Organization (WMO), there is now a 55% probability of La Niña conditions emerging between September and November, and a 60% chance between October and February. In its previous update, WMO had predicted a 60% likelihood of La Niña between July and September and 70% between August and November.

The WMO had previously expressed hope that La Niña's return could help moderate the high temperatures experienced globally in recent months, partly driven by the warming El Niño weather pattern, which has persisted since June 2023.

"Since June 2023, we have seen an extended period of exceptionally high global land and sea surface temperatures," said WMO Secretary-General Celeste Saulo in a statement.

Saulo cautioned that even if a short-term cooling effect from La Niña does occur, it will not alter the long-term trend of rising global temperatures due to greenhouse gases in the atmosphere.

La Niña is a natural climate phenomenon that cools ocean surface temperatures across large areas of the tropical Pacific Ocean, bringing changes in winds, rainfall, and atmospheric pressure. Its effects are often the opposite of El Niño, which warms ocean surfaces, leading to drought in some areas and heavy rainfall in others.

"Naturally occurring climate events such as La Niña and El Niño are happening within the broader context of human-induced climate change, which is increasing global temperatures, worsening extreme weather events, and altering seasonal rainfall and temperature patterns," WMO stated.

As in June, WMO reiterated on Wednesday that the likelihood of El Niño redeveloping in the near term is "negligible". Currently, "neutral" conditions prevail, meaning neither El Niño nor La Niña is present.

Despite this, Saulo warned that widespread extreme weather, including intense heat and heavy rainfall, continues to be observed. This underscores the importance of WMO's "Early Warnings for All" initiative, which aims to ensure that all countries have effective extreme weather warning systems in place by 2028.