Here comes La Niña: The little girl may pack big northern snows

Newsroom Long Range Forecast Here comes La Niña: The little girl may pack big northern snows

It’s time to talk about the weather and those twin weather-makers that make a difference in whether we’ll get more or less snow to slide on in different parts of the country. Their names are, of course, El Niño (little boy) and La Niña (little girl). They may be twins in one sense, but they have distinctively different personalities and are actually opposite climate patterns. Early predictions for the winter of 21-22 are that our little girl will win out.

What Is La Niña?

La Niña means that water temperatures in a large area of the central Pacific Ocean (around the equator) are below normal. These below-normal water temperatures influence global weather patterns, especially during the winter for the U.S.

This strong influence on winter weather is important because it provides some confidence in the seasonal snow forecast a bit ahead of the season’s start. Many people and even meteorologists are skeptical of long-range weather forecasts; especially those that purport to predict amounts of snow or rain for the next half a year. That skepticism is generally warranted—except perhaps during a La Niña (or even an El Niño) winter.

“The bulk of data suggests we’re headed into a cold phase also known as La Niña.  The most recent analog is last winter, which was also a La Niña winter,” writes OnTheSnow meteorologist Chris Tomer in his 21-22 Long-Range Weather Forecast.  “La Niña tends to organize the wintertime jet stream in a way that favors the Pacific Northwest and Northern Tier of states with the most consistent winter snowfall. La Niña tends to leave California and the Southern Tier of states drier and warmer than normal. This pattern is not conducive to atmospheric river setups.  The drought can deepen as a result.”

images of la Nina
Below normal water temperatures in the central Pacific Ocean give La Niña her fury. Image Courtesy of NOAA.

La Niña’s Impact On Previous Seasons

In the absence of La Niña (or El Niño), forecasts for an entire winter usually are not very instructive. However, when La Niña (or El Niño) influences the weather patterns, meteorologists often can provide a more confident seasonal forecast by looking at snowfall from past La Niña seasons. In short, La Niña gives us a historical guide to forecasting the future.

A La Nina winter
This Alta skier is knee-deep in a La Niña winter. Will it return? Forecasters are projecting a return of La Niña this winter. Image Courtesy of NOAA.

 

What Will La Niña’s Impact Be On This Season?

La Niña was the dominant weather force in the winter of 2020-2021. The Climate Prediction Center, a part of the National Oceanic and Atmospheric Administration (NOAA), released a forecast in July 2021 officially declaring a “La Niña Watch” for September to November.

Reuters news service reports that U.S. government forecasts predict La Niña weather conditions have a 70 to 80 percent chance those conditions will persist through the winter of 2021-22.

In his long-range forecast for OnTheSnow, Meteorologist Chris Tomer says that for the most consistent winter snowfall look to Whistler/BlackcombMount BakerStevens PassCrystalHoodBachelorTimberlineBanffSun PeaksFernie AlpineKicking HorseRevelstokeBridger BowlSun ValleySchweitzerWhitefishBig SkyJackson Hole, and Grand Targhee.

Winter Snowfall Outlook 2021-2022 (Graphic provided by Chris Tomer)

La Niña can persist for two years, but those seasonal forecast agencies who go in for long-range predictions are calling for fairly neutral conditions for the rest of 2021 into next summer.

La Niña Impact On The Future

Professor David Dilley of Global Weather Oscillations, GWO’s senior research expert says, “We can expect the severe regional cold outbreaks around the world to gradually expand and become more dominant and long-lasting during the next several winters.”

One of the first signs of global cooling was beginning during the 2020 winter, says GWS, across the high altitudes, stretching from Alaska across Central Canada to Greenland. Alaska experienced its coldest January and February on record.

Final Thought

Regardless of global climate patterns, there is a 100 percent guaranteed forecast for the winter: It will snow and you will have fun.

Here’s a fun fact: Who do weather watchers turn to for early predictions? To the Farmer’s Almanac, first printed in 1792. Almanac’s editors claim their forecasts traditionally have been accurate 80 percent of the time. When it comes to weather, we’ll take that.

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