A potentially strong El Niño climate pattern is expected to emerge this summer and persist for the rest of the year, according to the latest official forecast from the National Oceanic and Atmospheric Administration (NOAA).
Meteorologists estimate a 62% chance of El Niño emerging between June and August. El Niño occurs when trade winds weaken, allowing large volumes of warm ocean water to shift from the eastern Pacific toward the Americas.
“Although the evidence is still preliminary, this could be a very significant event in 2026 and extend into 2027,” says Daniel Swain, climate scientist at the University of California, Department of Agriculture and Natural Resources.
A strong El Niño would raise average global temperatures. The hottest years on record generally occur during active El Niño years, as this phenomenon happens when the eastern Pacific is warmer than normal.
“Its role in the global Earth system is to release heat from the ocean depths that was temporarily stored there,” says Swain. “El Niño allows that submerged heat to be brought to the surface.”
This dynamic manifested significantly in 2023 and 2024, when a long and intense El Niño pattern contributed to breaking global temperature records. 2023 set the record for the hottest year ever recorded on Earth, a record that was surpassed only by 2024 temperatures.
“If a strong El Niño develops, it will slightly increase temperatures in 2026, but will have a particularly large effect on 2027 temperatures, putting that year on track to likely be the hottest year on record after 2024,” says Zeke Hausfather, research scientist at Berkeley Earth and climate research lead at the tech company Stripe.
El Niño, which is a natural cyclical fluctuation, is just one of the factors driving this record heat. Global warming caused by burning fossil fuels, resulting from human activity, is the main reason for the planet’s warming. Even without El Niño, last year ranked among the three hottest years on record.
El Niño also affects regional climate patterns around the world. The southern United States typically sees more rain and milder temperatures, which can help control droughts and reduce wildfire activity.
However, the American Southwest faces such a severe drought that a rainier year will not be enough to fully replenish reservoirs, according to a new analysis from the National Integrated Drought Information System (NIDS). Additionally, the additional global heat caused by El Niño can lead to even more severe droughts in other parts of the world.
On the other side of the US, El Niño makes hurricane formation in the Atlantic Ocean more difficult, often coinciding with less intense hurricane seasons. However, El Niño offers limited protection, as a single large storm hitting the coast can cause catastrophic damage, and climate change has caused Atlantic temperatures to skyrocket, providing more fuel for storm formation. Additionally, El Niño does nothing to mitigate storms that form in the Pacific.
Swain says that El Niño’s regional patterns are its most dangerous effects. “This means more heat waves and notably higher temperatures, but perhaps most importantly what it means for everything else: more energy for storms, more intense rains, more severe droughts, more extreme wildfires.”
Source: npr.org