Project Winter: Winter Outlook 2021-2022
PEORIA (Heart of Illinois ABC) - Ready or not, here comes winter.
It’s that time of the year where I look into my magic 8 ball to see what Mother Nature may bring over the next few months. I look for clues in our ocean temperatures, past weather, upper level winds and much more. You need a place to start though, so why not begin with our weather right now?
So far this month has been colder compared to average. Recent trends tell us that this shouldn’t be too much of a surprise. Six out of the last ten Novembers have been colder than average. As we head into the winter months, seasonal trends actually get a little stronger. December and January have been warmer than average seven out of the last ten years, and February has been colder than average seven out of the last ten years. Climatology tells a convincing story, but our winter forecast isn’t as easy as that.
Our weather earlier this year also played a role in my forecast. Let’s rewind the calendar a few months to September and October. September was dry in Peoria and we had only 1.09″ of rain all month. That’s a little less than one third of the monthly average. October, on the other hand, was an extremely wet month. Peoria had its second wettest October on record with 9.68″ of rain. Our spring and summer seasons were also wetter than average this year.
For the next piece of the puzzle, we head to the Pacific Ocean. Chances are you’ve heard of El Niño and La Niña, but if you haven’t or you need a reminder, this is when the waters in the equatorial Pacific Ocean are either warmer (El Niño) or colder (La Niña) than average.
This winter, like last year, a moderate La Niña is expected. Since 1955, there have been 5 moderate La Niñas:
- 1955-1956, 1970-1971, 1995-1996, 2011-2012 and 2020-2021
Combined, these 5 winters produced slightly colder than normal conditions but less snow than average. While the average temperature was less than 1° below normal, there is a wide range in the extremes ranging from nearly 3° below average in 1970-1971 to almost 5° above average in 2011-2012.
While La Niña can be a main driver for our weather pattern, there are many other things to examine which can also play a role including:
- the water temperatures in the north-central Pacific Ocean (PDO or Pacific Decadal Oscillation)
- stratospheric winds (QBO or Quasi-Biennial Oscillation)
- what the jet stream and weather pattern over North America could look like (AO or Arctic Oscillation and NAO or North Atlantic Oscillation)
I even consider things such as where we are in the solar cycle (coming off of a bottom) and Siberian snow cover (above average) to help gives clues as well.
Lastly, I have to consider the fact that our world is warming and that the last decade or two has been much different than what we’ve seen 30 -50 years ago. For this reason, I gave more weight to recent years when selecting analog years. By doing this, I recognize that not every single analog year that I picked is a perfect match. Rather, I was able to put together a set of years with many similar characteristics that produced a similar trend which is reflected in my forecast.
Combining all of this information, I came up with the following analog set for this winter.
So now that I’ve discussed the nuts and bolts of how I got to my forecasts, let’s talk about the numbers.
This analog set gave a pretty clear signal - cold and snowy.
If you look at that analog set and the winters of 2010-2011 and 2013-2014 stand out to you, there’s a good reason for that. These two winters are numbers one and two for the snowiest on record in Peoria with 57.6″ (2013-2014) and 52.5″ (2010-2011).
I don’t think that our winter will be as severe, but I do expect a colder and snowier one compared to average. That doesn’t mean that we can’t have mild stretches at times, because that is certainly possible However, as a whole I think the winter season, defined as December through February, will be 1.5° to 2.5° below average.
Our average snowfall in Peoria is 26.2″, and I think we exceed that by about half of a foot with 30-36″ falling, counting from first flake to last.
Stay with the First Alert Weather Team throughout the winter for the latest and accurate snow forecasts!
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