The ‘triple-dip La Niña’ is on the way; and what that may mean for weather

This La Niña began in September 2020. 
The La Niña climate pattern is a natural cycle marked by cooler-than-average ocean water in the central Pacific Ocean. It is one of the main drivers of weather in the United States and around the world, especially during late fall, winter and early spring.

La Niña is back for the third year in a row. The meteorological system over the Pacific Ocean that can influence weather patterns worldwide is projected to continue through the end of the year.

It’s the first time this century that La Niña has returned for three consecutive years, according to the World Meteorological Organization, a U.N. agency. La Niña occurs when strong winds blow warm water on the surface of the Pacific Ocean near the coast of South America across the equator toward Indonesia, other parts of Asia and Australia. That causes cooler water to rise to the surface of the Pacific Ocean, which has wide-ranging ripple effects on the weather.

A typical La Niña winter in the U.S. brings cold and snow to the Northwest and unusually dry conditions to most of the southern tier of the U.S., according to NOAA’s Climate Prediction Center. The Southeast and Mid-Atlantic also tend to see warmer-than-average temperatures during a La Niña winter.  Meanwhile, New England and the Upper Midwest into New York tend to see colder-than-average temperatures, the Weather Channel said.

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The southwestern U.S., with rain clouds pushed out to sea, becomes drier than usual. Northwestern U.S. states and Canada see cooler-than-average temperatures, rain and flooding.

Australia, Indonesia and other parts of Asia also experience heavy rainfall. La Niña can even cause more lightning activity in the Gulf of Mexico and along the Gulf Coast and increase the number of hurricanes and tropical cyclones, according to the National Oceanic and Atmospheric Administration.

We are in a La Niña Advisory and it is favored to continue through the upcoming winter. This would be a rare third winter in a row for this colder water phenomenon in the Pacific Ocean which can have a big impact on the winter weather across North America. This includes everything from snow to tornado outbreaks. According to the World Meteorological Organization, it is also being credited for mitigating or cooling global temperatures. “It is exceptional to have three consecutive years with a la Niña event. Its cooling influence is temporarily slowing the rise in global temperatures – but it will not halt or reverse the long-term warming trend,” Petteri Taalas, the secretary-general of WMO, said in a recent report.


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