Super El Niño, Polar Vortex Collapse Could Hit US At Same Time

Two major atmospheric phenomena could influence U.S. weather in the coming weeks as a super El Niño continues to strengthen in the Pacific Ocean, while the Arctic polar vortex undergoes an unusually early collapse. The weather patterns could interact in the coming weeks. The super El Niño, which is characterized by warmer-than-average waters in the equatorial Pacific and weakened trade winds, has been strengthening for months. National Oceanic and Atmospheric Administration (NOAA) forecasters anticipate it will reach peak strength this winter.

Meanwhile, meteorologists are also drawing attention to the collapsing polar vortex, a large area of cold air and strong winds, over the Arctic. Read More on Weather WFLA-TV chief meteorologist Jeff Berardelli said the collapse appears to be the earliest on record, occurring roughly a month earlier than previously observed, while the super El Niño has already become the strongest on record. Competing For Influence The two phenomena are not opposing weather patterns, but they can exert competing influences, with El Niño tending to favor broader warmth while a weakened polar vortex can produce periods of Arctic cold.

Typically, polar vortex disruptions occur mid- to late winter, AccuWeather long-range meteorologist Alex DaSilva told Newsweek on Friday, and since this event is occurring so early, there won't be as much cold air to work with. "I don't think the cold outburst is going to be that significant compared to if this happened during the heart of winter," DaSilva said. Still, below-average temperatures are expected across the northern Midwest and Northeast during the first week of November.

It has been warm and dry across those regions in recent days. However, the colder temperatures will be short-lived. Overall, El Niño's influence on U.S. weather will win out in November, DaSilva told Newsweek , with above-average temperatures expected during the rest of the month. ... What Is El Niño? El Niño is the warm phase of the El Niño-Southern Oscillation (ENSO) cycle. It occurs between every two to seven years and typically lasts between nine and 12 months, although a particularly strong El Niño can last longer.

It is characterized by unusually warm ocean temperatures in the equatorial Pacific and weakened trade winds, which can influence weather around the globe in different ways. This year's El Niño has already broken records in terms of how far above average the ocean surface temperatures have risen. A stronger El Niño can be associated with stronger storms. The El Niño can influence weather patterns around the globe. In the U.S., it typically brings warmer, drier weather to the northern regions during the winter months, with wetter, stormier conditions expected across the South.

Increased snowfall is expected over the Intermountain West and high elevations of the U.S. Southwest this year as well. What Is the Polar Vortex? The polar vortex is large area of cold air and low pressure surrounding Earth’s poles, according to the National Weather Service. It is present year-round but weakens during the summer months and strengthens during winter. The vortex often expands during winter, sending blasts of Arctic air southward over the U.S., the agency says.

"A split vortex can push some of the cold air locked up over the Arctic down into the mid-latitudes, usually 1 to 3 weeks later. That doesn’t guarantee a big cold blast for us, but it’s definitely on the table as we head into the 2nd half of November..." meteorologist Max Velocity posted on X on Thursday. View this post on X How Will Polar Vortex Collapse Change US Weather? When the polar vortex weakens, it can allow for cold, Arctic air to descend into the U.S., particularly the northern regions.

The polar vortex normally strengthens during this time of year, but forecast models are now showing weakening stratospheric winds. If the polar vortex continues to weaken like the models predict, it could lead to the earliest major sudden stratospheric warming (SSW) on record, Berardelli said. When the air in the stratosphere warms suddenly during a SSW event, it can disrupt the polar vortex, which allows the frigid air to spill southward into the U.S. a few weeks later.

"Why does it matter? Well, a disrupted polar vortex can increase the chances of Arctic air spilling southward into the United States, Europe and Asia in subsequent weeks," Berardelli said in a post on X on Friday. "However, that outcome is far from guaranteed because El Niño is overwhelming the pattern." View this post on X Berardelli went on to say the early-season disruption could be connected to the super El Niño , as the climate pattern can cause changes in the stratosphere, which can then disrupt the polar vortex.

What Happens Next While below-average temperatures could be felt across the Midwest and Northeast during the first week of November, the rest of the month is still expected to be above-average because of El Niño's influence. DaSilva stressed that the early disruption to the polar vortex does not indicate whether or not another disruption will occur later in the winter when temperatures are colder and more impactful, but AccuWeather meteorologists are still forecasting a "very warm" Northeast and northern Midwest this winter.

"El Niño will still be the primary driver behind this winter because it's so strong," DaSilva told Newsweek . Contact Newsweek editor on this story: Edward Pearcey.