Hurricane season could be 'extremely active' with arrival of La Niña
Janet LoehrkeThe switch is on.
The El Niño climate pattern is transitioning toward La Niña, according to the National Oceanic and Atmospheric Administration.
La Niña is expected to impact the hurricane season's activity. There's a 60% chance La Niña will form by June into August, and a higher chance by fall.
That outlook is consistent with recent projections of a 2024 hurricane season that will be "extremely active," according to Colorado State University.
What is La Niña?
There are two extremes of reoccurring climate conditions – La Niña and El Niño – that can influence weather globally.
The climate phenomenon known as La Niña − "little girl" in Spanish − is projected to form in the Pacific Ocean later this year.
Typically, jet streams created by La Niña are considerably unpredictable and can cause intense weather conditions. When storms and rainfall in the western Pacific push a weaker jet stream northward, it can lead to drought in the southern U.S. and cooler temperatures, heavy rains and flooding in the Pacific Northwest.
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How does La Niña influence hurricanes?
When the surface temperatures of the Pacific Ocean near the equator are lower than the long-term average, it's known as La Niña. El Niño – "little boy" in Spanish, her brother – is a climate phenomenon that results from those waters being warmer than usual.
The lower surface temperatures could mean warmer, drier weather throughout the southern region of the U.S. and the potential for a "hyperactive" hurricane season in the Atlantic basin this year, with one forecast expecting as many as 33 named storms. An average year sees 14.
More:When is Atlantic hurricane season? Here's when stormy conditions will start and end.
The yin and yang of La Niña and El Niño
When surface temperatures in the tropical Pacific Ocean drop by roughly 0.9°F (0.5°C) over the span of three months, a La Niña occurs. The reverse – an El Niño – results from warmer-than-normal temperatures. The three-month rolling average temperature anomaly – difference from average – is shown in the chart below.
What would a La Niña winter be like?
La Niña is expected to persist into next winter, according to forecasters. According to NOAA's Climate Prediction Center, a typical La Nina winter in the U.S. brings cold and snow to the Northwest and extremely dry conditions to most of the South.
SOURCE National Oceanic and Atmospheric Administration, Reuters, Detroit Free Press and USA TODAY research
CONTRIBUTING Doyle Rice and Ramon Padilla/USA TODAY
More:Get ready to hear a lot about La Niña. Here's why it could make hurricane season worse.