It is all over too soon. After weirding out weather all around the world, this winter’s monstrous El Niño may be on its way out. Though more data is still forthcoming, NOAA has described this year’s El Niño as at least on par with the 1997-1998 El Niño event, the strongest on record. As El Niño bids us farewell for a few years, a brief period of calm will be followed by a reactionary natural force called La Niña. Sometimes described as the anti-Niño, La Niña is expected to cool sea surface temperatures where El Niño had warmed them. The effects of such a shift may strike weather-weary humans and ecosystems with whiplash.
La Niña is expected to produce cooler, wetter weather in the northern United States while the southern United States will become warmer and drier. This would seem to return to the regions some “normal” weather, though such a drastic shift may not feel normal. However, the felt impact of La Niña depends on when the weather system reaches its zenith. La Niña may feel more intrusive if it begins in the colder months, especially following a warm winter, and is less likely to make as dramatic an impact if it occurs during the summer. NOAA currently projects that there is a 50 percent chance that La Niña will arrive by the end of the summer this year. If not, there is an 80 percent chance that her arrival will come next winter.
The jury is also out on how strong La Niña will be when she does arrive. “We’re reasonably confident that we’ll see one, but plead ignorance on how strong it will be,” says NOAA forecaster Huug van den Dool. While projecting La Niña is challenging, the 1997-1998 El Niño season could provide clues into what this year’s event may bring. Following the powerful El Niño in the late 90s, the world experienced an equally potent La Niña.