Official: NOAA officially declares the end of the La Niña phenomenon. What impact will this have on the weather in the coming months?

Arab Weather - The U.S. National Oceanic and Atmospheric Administration (NOAA) announced the end of the La Niña phenomenon, which lasted only a few months, confirming that the tropical Pacific Ocean is now in an ENSO-neutral state. The agency expects this condition to continue through the Northern Hemisphere summer, with a probability of more than 50% that the neutral state will prevail through the fall.

What is the Southern Oscillation and what does "neutral" status mean?

The Southern Oscillation is a pattern of changes in ocean surface temperature and atmospheric circulation in the tropical Pacific Ocean.
La Niña is characterized by lower-than-normal sea surface temperatures, stronger trade winds, and less rainfall in the central Pacific Ocean. In contrast, El Niño is characterized by higher sea surface temperatures, weaker trade winds, and increased rainfall in the central and sometimes eastern Pacific Ocean.

These two phenomena influence global weather and climate patterns, including temperatures, rainfall, snow, tropical cyclones, and other weather events. Because El Niño and La Niña can be predicted months in advance, they provide an early picture of seasonal forecasts. A neutral state means that neither El Niño nor La Niña is dominant, making climate forecasts less clear.

Reasons for the end of the La Niña phenomenon

According to NOAA, over the past month, neutral conditions were expected to develop, and they did.
A decline in low temperatures in the central Pacific Ocean, coupled with the westward extension of very warm waters in the Far East, contributed to the disappearance of the cold water effects associated with the La Niña phenomenon.

The subsurface waters, which had been cooler than usual in recent months, have recently begun to evaporate, supporting the end of the phenomenon. It's worth noting that ENSO is an integrated system between the ocean and the atmosphere, and for the phenomenon to be classified, distinct changes in both aspects are required.

The importance of long-term averages in understanding Pacific Ocean changes

Estimates are based on periodic averages. Currently, the period 1991–2020 is used as a reference, and this average is updated every five years to account for changes in the Pacific Ocean.

Because the last La Niña did not last for five consecutive seasons above the -0.5°C threshold, it is not officially considered an event in historical records.

Forecasts for the remainder of 2025

The ENSO-neutral condition is expected to persist through the summer. As fall approaches, the probability of La Niña reappearing increases, reaching twice the chance of El Niño, but neutrality remains the highest probability for the onset of winter.

These forecasts are based on computer models, most notably the North American Multi-Source Model Ensemble (NMME), which show a variety of outcomes later in the year, with most forecasts falling within the neutral range.

Currently, NOAA is bidding farewell to the La Niña phenomenon and declaring the world entering a phase of climate neutrality. With the end of the La Niña phenomenon, temperatures and rainfall will often be around their usual levels in various regions of the world, God willing...

And God knows best.