By Brian K. Sullivan
The odds of a La Nina comeback later this year are rising, lifting prospects of the weather-changing pattern that’s blamed for droughts and hurricanes returning for a third straight year.
The outlook hints at “a re-strengthening of La Nina conditions again in the fall and upcoming winter,” the US Climate Prediction Center said Thursday in its latest forecast.
The chances of La Nina returning between November and January have climbed to 61%, up from its April estimate of a 53% chance of a comeback, the agency said in its report. Forecaster Michelle L’Heureux sees a growing chance that La Nina could return for its third winter, which she said would be only the third time that has happened since 1950. Three-peats occurred between 1973 and 1976 and from 1998 to 2001, according to the National Oceanic and Atmospheric Administration.
La Nina brings havoc to global weather patterns. The phenomenon can divert Pacific storms away from California and other West Coast states during the North American winter, amplifying drought conditions in the region. In the Atlantic, La Nina’s impacts can cut down on wind sheer in the heart of hurricane season and allow more storms to form and strengthen. Forecasters predicting an active hurricane season this year have cited conditions in the Pacific for their call.
The current La Nina has been around since October and followed an earlier La Nina that circulated in late 2020 before fading last summer. This latest version unexpectedly strengthened in April, giving the equatorial Pacific Ocean its coldest April in records going back 72 years -- a sign the phenomenon still has some punch.
“We’re just as strong now as we were at the peak this past winter, so it is kind of eye opening,” L’Heureux said in an interview. “It is currently pretty impressive, but we are not forecasting that to last.”
There are signs temperatures in the Pacific could return to normal in the next few months as warmer water builds below the surface and trade winds start to weaken, she said.
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