Peoria, Ill. (WMBD) – We’re nearing the halfway point of meteorological winter (December through February) and many snow lovers are asking, “where’s the snow?”. In this article we’ll take a look at what we’ve seen so far this winter and what could evolve down the road.
There’s no question the season has been off to a warm start and snowfall has been below average. A breakdown of our temperature departures from average since December 1st show that our temperature across much of Illinois are indeed above average. While December started off warm, the frigid temperatures towards the end of the month offset much of that warmth resulting in near to below average temperatures statewide.
Since the start of January temperatures have once again soared, and through the first 11 days of the month the entire state is experiencing temperatures well above average. In Central Illinois, our January average temperature ranges from 10° -13° above average as of January 11th. You can view the average temperature departure maps in the slide show below.
As many in Central Illinois have observed, we have not had a lot of snow this winter season. In fact Peoria’s biggest snow of season was 2.8″ that fell between November 15th-16th. Since then, we’ve only had one other snowfall that exceeded an inch and that was the December 22nd cold front that brought Peoria 1.7″ of snow, very cold temperatures, and a lot of wind. Every other snow event has only produce a few tenths of an inch of snow.
As of January 11th, most of the area has received anywhere from 2.0″ to 8.0″ of snow this season with Peoria seeing some of the highest amounts at 7.6″. That means most of the area is somewhere between 2.5″ and 7.5″ below average for the season. The biggest snowfall deficit is across northern Illinois where they are currently experiencing snowfall deficits over 10.0″ in spots. You can view our snowfall amounts and departures from average in the slideshow below.
How Mild or Severe Has This Winter Been?
According to the Accumulated Winter Season Severity Index (AWSSI), which factors in temperature, snowfall and precipitation data, Peoria’s winter so far is considered “Moderate” which is between “Average” and “Mild” on the severity index.
Looking at Peoria’s current AWSSI chart you can see that the two main jumps in the index came with the only two winter storm’s we’ve had, the mid-November snow event and the late December arctic outbreak. Both systems sent Peoria’s AWSSI score into “Severe” territory for a brief period of time. However, the warm and relatively snow-free weather since then has kept our AWSSI value low.
If you compare our current AWSSI value to those from the previous five years you find this winter has not been all that different. In fact, four of the last five winters had the same or lower AWSSI values at this very same point in the winter season. With the exception of the 2019-2020 winter season, the other three winter’s ended up near average, or even severe, after experiencing more cold and snow in February.
Looking back at our snow stats from our past five winters you can see how starting with below average snowfall doesn’t necessarily mean it will end that way.
|Season||December – January 11th Snowfall||February|
|Seasonal Total||Season Departure From Average|
Believe it or not, so far this season we’ve actually received more snow than our past two winters had at this point in the season. Despite the quiet starts each season doubled (nearly tripled) their seasonal totals in the month of February which ultimately resulted in seasonal snowfall totals ending near to above average. Is there a chance we do it again and make up some ground in February? It’s certainly possible.
For reasons I can’t explain, the month of February has turned into a pretty snowy month. With an average of 6.9″ of snow, February is Peoria’s second snowiest month of the year. However recent Februaries have proven to be snowier than average, so much in fact that 8 of Peoria’s top 10 snowiest Februaries have occurred since 2000 and the top 5 have all occurred after 2008. You can see those stats below.
|(Ranking) Year||February Snowfall Amount|
Why Has January Been So Mild?
Our recent stretch of mild weather can be linked back to a few things.
- A strong jet stream over the Pacific Ocean
- A strong Polar Vortex over the arctic
- A lack of very cold air in Canada
The strong jet stream over that Pacific Ocean has been responsible for bringing torrential rains and heavy mountain snows to California, but it has also impacted weather across the rest of the United States. Associated with a strong polar vortex, the strong west-east oriented jet stream has prevented any significant down stream amplification of the jet stream over the U.S. This means that storms moving on shore in California are generally moving due east and are milder than storms that drop in from the north.
Since temperatures in Canada have generally been above average, there’s no “local” source of cold air that can keep lower latitudes cold for a prolonged period of time. So while storms come through and produce a little bit of snow, there’s typically not enough to produce a significant winter storm.
What Might We Expect for the Rest of the Month?
While the storm track remains active, temperatures are generally expected to remain above average over the next few weeks. The next storm system to impact the area will come Sunday night and Monday bringing widespread rain to Central Illinois.
The Climate Prediction Center’s 6-10 Day forecast continues to highlight a high likelihood of above average temperatures and above average precipitation from January 18th-22nd. A lot of that seems to stem from another storm system that is likely to track across the area between January 18th and 20th. Despite average temperatures being above normal during the period, it can still be cold enough to support snow. Depending on the eventual storm track, this system offers up the next best chance of accumulating snow across the area.
Towards the end of the month model guidance suggest we could see a return to a colder and snowier weather pattern that could last into the first part of February, but confidence remains low. As we’ve seen over the past few years, it’s not unusual for winter to end with a bang as we enter the month of February and I wouldn’t be surprised to see that play out again this year.