The upcoming El Niño season is forecasted to bring high sea levels and potentially powerful winter storms to Southern California, but another component of that natural phenomena is also headed to the region.
A Kelvin wave is currently moving along the coast of Mexico, and it’s expected to reach California by next month.
What is a Kelvin wave?
Kelvin waves originate far away in the Western Equatorial Pacific Ocean. They’re a foundational component of what drives El Niño and the massive amount of warming happening in the Eastern Equatorial Pacific.
A major Kelvin wave moving across the Pacific is expected to arrive in SoCal next month, raising sea levels by 6 to 12 inches.
Kelvin waves form when trade winds weaken. When those winds stop blowing, which typically happens every 4-7 years, warm water that accumulates in the ocean starts moving back toward California and South America.
That surge of water is not a tsunami, but the Kelvin wave will raise the sea level up to 5 to 10 inches.
Although the wave itself won’t be noticeable to swimmers or boaters, it will be if it arrives during a storm or high tide. California’s coastline could see even higher water levels as El Niño continues to strengthen.
The Kelvin wave is expected to make it to Southern California by early October.
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