‘Behemoth’ El Niño to upend global weather, UN warns

'Behemoth' El Niño to upend global weather, UN warns Extreme weather events already being documented are anticipated to "multiply – and cascade – as El Niño intensifies, " the World Meteorological Organization cautioned.

Key points

• In the United States, a particularly robust El Niño tilts the odds toward stormier weather throughout the South, remarked Ken Graham, director of NOAA's National Weather Service.
• "This will certainly be an historic El Nino, " Michael Mann, a climate scientist and professor at the University of Pennsylvania, informed USA TODAY.
• This El Niño is already at record strength and is projected to continue to intensify over the next few months, NOAA's Climate Prediction Center has stated.
• As ocean temperatures continue to warm in the eastern Pacific, the World Meteorological Organization (WMO) cautioned on Oct.
• East Africa: Wetter-than-normal conditions probable during the October-December rainy season, increasing worries regarding heavy rainfall and flooding.

Kelvin waves travel underwater and tend to occur during El Niño weather conditions. Chief Meteorologist Mark Tamayo explains how incoming 'Kelvin' waves may impact the Bay Area's coastline this winter.

Meanwhile, the warnings regarding El Niño continue to roll in. The United Nations' weather agency weighed in on Oct. 21, calling the potent climate pattern a "behemoth" and a "wrecking ball."

"It will tear through Latin America, Eastern and Southern Africa, Asia and the Pacific with extreme heat, droughts and flood, " the U.N.'s Tom Fletcher remarked, warning of profound humanitarian consequences.

El Niño, a natural warming of Pacific Ocean waters that affects weather and climate patterns worldwide, tends to cause higher global temperatures and disrupt rainfall patterns throughout substantial regions, meaning drought in some areas and heavy rains in others.

It triggers disruptive weather patterns that often impact agriculture, infrastructure and supply chains, potentially causing trillions of dollars in damages around the globe.

"This will certainly be an historic El Nino, " Michael Mann, a climate scientist and professor at the University of Pennsylvania, informed USA TODAY. It will be the "biggest event on record, " but since reliable records only go back less than a century, it's challenging to assess how unusual it is in a longer-term context, Mann noted.

As ocean temperatures continue to warm in the eastern Pacific, the World Meteorological Organization (WMO) cautioned on Oct. 21 that the developing El Niño could be "unprecedented in strength."

"This is literally off the monitoring charts that we have used for the past four decades, " remarked Celeste Saulo, secretary of the WMO. The event is forecast to peak afterwards in 2026, "but its impacts will be felt long after that, " Saulo stated.

For context, the WMO expects the El Niño event to become extremely solid, with temperatures in the central Pacific rising more than 6 degrees (3.8 Celsius) above normal between November and January, peaking around December.

Global financial impact: 'Super El Niño' will have an alarming financial impact, experts fear.

Extreme weather events already being documented are anticipated to "multiply – and cascade – as El Niño intensifies, " the WMO cautioned.

Forecasts for the event are "very high confidence now and the very strong El Niño will certainly last through the next several months, " remarked Emily Becker, deputy director of the Cooperative Institute for Marine & Atmospheric Studies at the University of Miami's Rosenstiel School for Marine, Atmospheric & Earth Science.

El Niño is projected to strengthen further, but at this point, forecasters already have as much information as they'll ever have concerning the projected impacts, and the seasonal outlooks reflect that, Becker remarked. She continued that it's "important to remember that the weather is always full of surprises, and even in a strong El Niño it's critical to monitor short-term weather and sub seasonal forecasts." El Niño adding to climate change effects.

One of the significant things to note concerning this El Niño event is that it's converging with the impacts of human-caused climate change, such as sea level rise, noted Fraser Shilling, director of the UC Davis Road Ecology Center, at the Institute of Transportation Studies, in a lately published study for California.

El Niño warming "adds to human-caused warming in such a way that we see new records set every time we get a major El Nino event, " remarked Mann. He was a lead author on a study published earlier this year that identified El Niño "contributed substantially to the record 2024 global temperatures."

"The science is very unclear about whether we are seeing or expect to see an increase in the amplitude of El Nino events from human-caused warming, " Mann remarked, with numerous models predicting the opposite will occur.

Meanwhile, the extreme levels of warmth associated with major El Niño events are temporary, he remarked, but the events such as those discussed in the United Nations announcement provide us a glimpse of "what our future will look like if we continue to warm the planet." US impacts from El Niño.

In the United States, a particularly robust El Niño tilts the odds toward stormier weather throughout the South, remarked Ken Graham, director of NOAA's National Weather Service. Graham cautioned the nation earlier in October to prepare for its impacts. "While higher chances of rain and snow may bring relief to drought-afflicted areas, too much precipitation on dry soil can fuel destructive flash floods and mudslides, " he remarked.

In California, Gov. Gavin Newsom lately declared a state of emergency to prepare for the impacts from the event.

As the report notes Shilling issued, shoreline flooding already seen along the Southern California coast with this El Niño raises reservations for the coming months. California's Highway 37 and other coastal roadways are "extremely vulnerable to floods and failure during this winter's coming El Niño, " Shilling remarked. "It's important to be informed of risk so you can make decisions." WMO report details global impacts. The WMO's outlook cautioned of the after potential impacts this winter.

While drought risk increases in parts of Central America, the southern Caribbean and the Amazon, the Americas: Rose rainfall in the southern parts of western South America and in portions of North America and the northern portion of the Caribbean.

Southern Africa: Rose risks of drier conditions could affect crop production, water availability and livelihoods from the typical start of the rainy season in November.

Southeast Asia: Warmer conditions and rainfall deficits growth the risk of heat exposure and place further pressure on agriculture and water supplies, like the growth in wildfire and smoke-haze risks we are already seeing.

Doyle Rice and Dinah Voyles Pulver are national correspondents for USA TODAY, focusing on climate and weather. Reach them at [email protected] and [email protected]. SMS Facebook Twitter Email. Share your feedback to support improve our site! Share your feedback to support improve our site!

In short, behemoth El Niño to upend global weather, UN warns is the central thread here, and readers can expect follow-up reporting as the picture becomes clearer.