![]() Stacking my set of analog years with La Niña winters in general and the climate norms (1981-2010) shows great results for snow lovers. You can see how the current index (dotted black line) has a very similar trajectory to my analog years. I call this set my analog years since they most closely resemble our current ENSO pattern based on our current Oceanic Nino Index (ONI).Īn ONI index of -0.5 to -0.9 shows a weak La Niña, -1.0 to -1.4 is moderate, and -1.5 to -1.9 is a strong event. This year, we are skirting along a weak La Niña pattern. I also took a closer look at five specific La Niña winters for more hints this winter. In fact, data suggests we could see nearly double the amount of snow compared to normal. There is evidence that more snow tends to arrive in these patterns. Let’s take a look at averages across 10 second-year La Nina winters since 1950. Could we possibly see some impacts from that? This winter is special because it will be a back-to-back La Niña winter. Second-Year La Niña trends: Could we see more snow? One of, if not, the most defining characteristic of an upcoming winter is through the lens of the El Nino Southern Oscillation (ENSO). That’s because oceanic and atmospheric circulations are coupled, often impacting each other by shifting blobs of water and air masses around. Due to persistent below-average sea surface temperatures across the eastern equatorial Pacific Ocean, La Niña conditions have emerged this winter. A La Niña pattern tends to provide cooler and wetter weather across the Pacific Northwest during wintertime as colder storms drive into the region from the north. These are my thoughts for the 2021-2022 winter outlook: Tracking Previous La Niña Winters in Portland There are lots of numbers and graphs to ingest in here… but please, stick with me. Most long-range seasonal forecasts are built using a combination of these cues and weather trends over previous decades.Įvery year in October, I set aside a week of my time to dive into 80 years worth of data on Portland’s winter trends. There are methods of analyzing these complex signals to help provide some sort of winter outlook, even if the snow is still a few months away. However, we are at a point in the year where oceanic and atmospheric patterns can provide signals for winter season activity. What does that mean for snow in Portland or snow in the Cascade mountains? Could we see a second winter in a row with 10.1 inches of snow in the city? If I really knew the answer to those questions, in October, I’d be rich! It’s simply too early to forecast that far out with accuracy. (KOIN) – For the second winter in a row, La Niña conditions are expected to persist through February 2022 and bring impacts to precipitation and temperature across our region. ![]() Things look particularly bad for the drought in the Southwest, where drought conditions are forecast to worsen over the next few months.PORTLAND, Ore. This signals a wetter winter for parts of the Midwest and the Tennessee Valley, but drier conditions across the southern U.S. ![]() Gottschalck said this year’s La Niña looks like it will be a moderate (or upper-end moderate) La Niña pattern. Drier-than-average conditions are favored in south-central Alaska, southern California, the Southwest, and the Southeast. (NOAA based on NWS CPC data) La Niña and Droughtįor the second winter in a row, La Niña conditions are forecast to affect the country’s winter weather, said Gottschalck. Winter Outlook map for precipitation shows wetter-than-average conditions are most likely in parts of the North, primarily in the Pacific Northwest, northern Rockies, Great Lakes, Ohio Valley and western Alaska. This precipitation forecast has a lot do with La Niña, which has already started to settle in.
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