Winter forecasting is one of the biggest challenges that any meteorologist encounters. In general, any type of long-range climatological forecast poses great obstacles. However, we are able to see certain signals that will allow us to make an educated guess to what the next 3 months may look and feel like.
For years forecasts have been put out from various organizations. I always enjoy looking at some of these from places like the “Farmer’s Almanac” as seen below.
Or maybe you are a fan of the “Old Farmer’s Almanac”. Why there are 2 different ones I’ll never really know but for entertainment purposes they are fun to read especially when they use “icky” to describe a forecast for a region.
NOAA each year puts out a little less specific forecast, basically eluding to what the probability is for warmer or cooler than normal temperatures. As seen below, we get “equal chances” in our area. Which means, eh it could go either way.
The NOAA precipitation outlook leans more towards a wetter pattern for us as displayed by the green area corresponding to wetter than normal conditions for the Great Lakes region.
As many of you already know, we’ve had quite the start to winter already. Or have we? Technically it isn’t even winter yet but we’ve picked up a little over 2″ of snow in Champaign so far. Compare that to the just .2″ of snow in Anchorage, Alaska so far this season.
One key component that we’ve learned to have a good correlation to our weather comes from the ENSO pattern. We can use this to determine how or weather may play out over the winter season.
There are 3 different patterns we can be in as shown below. We look at the ocean temperatures and whether or not they are cooler or warmer than normal or sometimes neither.
This year, the waters near the equatorial Pacific are neither colder nor warmer resulting in what is known as a LA NADA, or basically a neutral pattern for us.
Forecasters have models that project how ocean waters will change over the next year and as seen on the graph below the “neutral” forecast is showing a very high likelihood of sticking around for our winter.
Luckily we can go back and look at data over the last several decades allowing us to compare and contrast winters with similar conditions. The table below shows the different patterns of ENSO.
We can then go back and find years where ocean water behaved in a similar way allowing for at least a small glimpse into possible pattern forecasts for us during the winter season.
While the ENSO pattern is just one of many different indices that we can use, it is one that most easily can be used to look back at those similar years in terms of temperature and precipitation.
For example, I just went back to look at the past 10 years snowfall in Champaign and then looked for years where we were in a neutral pattern.
Most recently, I found the years below. 2012-2013 and 2014-2015. These are called analog years and can be used to make comparisons. For example those years saw slightly above average snowfall.
Another factor that show correlation is what the sun is doing. We go through 11 year solar cycles and right now we are at a minimum. This can be connected to sometimes colder patterns.
Snowpack across Canada and Siberia play an important role in our weather here as displayed already in November. An early and deep snowpack has led to early season cold spilling down in much of the US.
Looking at that deep snow pack allows us to see just how much cold air might be and stay in place. More snow, means more cold.
That cold air has already plunged down well south of where it usually would be for this time of the year a few times already this season.
Officially my forecast for temperatures this season is for below average readings over the next 3 months.
I think temperatures will be about a degree to a degree and a half below normal.
When it comes to snowfall, we average about 23″ for the year and I think we might just slightly beat that out.
Above normal snowfall is likely as many of our neutral years we’ve seen impressive snowfall amounts. I think plenty of cold air will be available along with an active storm track giving us opportunities for the white stuff.
I won’t get too out of control with the snowfall, but will say a good 25″ is possible with maybe even higher amounts in isolated areas.
In the end, time will only tell how things will play out but I would say to stay on guard this winter season as we’ve still got a long way to go before we can start talking about spring!