NOAA Releases Winter Outlook: La Niña Impacts Expected
Every autumn, the National Oceanic and Atmospheric Administration (NOAA) releases their season outlook, with projections of what we can expect (weather-wise) into the winter season. This isn't your daily weather forecast; It's probabilistic insight into the longer term temperature and precipitation patterns on the scale of months. The outlooks are based on global weather patterns, which decades of research have proven that weather on one side of the globe, can impact weather thousands of miles away.
This year, NOAA's winter forecast favors warmer, drier conditions across the southern tier of the U.S., while cooler, wetter conditions remain in the north. Above average temperatures and precipitation are also expected for Hawaii, and western Alaska.
We're about to get deep into the meteorological nerdiness of why the outlook shows what it does. NOAA says La Niña will play a large role in North America's 2020-2021 winter season. La Niña is a phenomenon in the equatorial Pacific Ocean, where sea surface temperatures remain colder than average. La Niña's presence causes shifts in the jet stream, or the global "river of air", that generally dictates storm track patterns and the divide between colder air (to the north), and warmer air (to the south). La Niña impacts the weather patterns across North America, and the entire globe, especially during winter.
While the outlook does not specifically call out snowfall, we can look for areas with wetter and colder expectations and assume snow would be more likely to occur. Generally, this setup would mean that western Canada, the Pacific Northwest, Northern Rockies, through the Great Lakes would be the snowiest areas this winter.
We can also look at past winters to see how snow panned out under a similar pattern setup. Research on snowfall patterns in North America during La Niña winters show better chances for snow across western Canada, the northern and central U.S. and Eastern Canada.
Don't worry, northeast, it doesn't mean no snow at all. We can still get huge snowstorms and nor'easters during La Niña winters in the northeast. Cold air can still intrude on the overall generally milder conditions, which means forecasts days out can better predict details of the rain/snow line with any incoming storm. In a La Niña winter in the northeast, it's best to monitor forecasts one week at a time to find the snow. Good thing we have SnoCast forecasts to help us there.
Okay, okay.... We've dug deep enough into the meteorological meat of the upcoming winter. We know, based on every season, snow will come and we will have excellent days on the slopes. And we can't wait to hit the trails this season, no matter what Mother Nature throws our way.