GRAND RAPIDS, Mich. (WOOD) — Another winter season is upon us, with months of mystery ahead.
In the last decade, we have seen both the fiercest season on record (2013-2014) as well as the least snowy in the last 30 years. This year looks to be primarily ruled by a La Nina, but there are so many secondary factors that will almost certainly complicate the season.
Here are the big takeaways for the 2020-2021 winter forecast:
BIGGEST PLAYERS THIS YEAR
Any time there is a strong signal in the equatorial Pacific related to the El Nino Southern Oscillation, it is worth looking at for the upcoming winter season. ENSO events are known better as El Nino phases and La Nina phases.
When ENSO is in a certain phase, it can change the stormtrack over the United States significantly and alter the outcome of our winter season.
This winter season, a moderate strength La Nina has formed. La Nina years typically feature wetter-than-average conditions through the winter for West Michigan, but this doesn’t always mean the moisture falls as snow.
“Moderate La Nina years are typically marked by a transient pattern. This makes this year’s winter forecast quite a challenge. The Great Lakes typically receive above average precipitation but how many times will we be on the northern or southern side of the storm? The Groundhog day blizzard in 2011 was an example of this when we received an historical snow event. Even with that event, the season snowfall for Grand Rapids turned out to be average.” says Meteorologist Matt Kirkwood.
Here is an example of the big variation in snowfall totals on previous La Nina event years:
Average for us here in West Michigan is typically around 75 inches of snow in Grand Rapids, with higher amounts near the lakeshore because of the lake-effect snow belt.
The sea surface temperatures south of Alaska are also usually quite important to our snow forecasts each season. Warmer-than-average temperatures in the Gulf of Alaska tend to push the jet stream further north over the western U.S. and can often trigger a dip over the Great Lakes. When this occurs, the dip in the jet stream frequently allows for more cold air intrusions and the chance for more lake-effect snow events.
LAST YEAR IN REVIEW
Last year’s winter forecast fell short. It was one of the least snowy seasons on record, although West Michigan did see quite a bit of snow in February.
“November was 5.5 degrees cooler than average (and more than 10 degrees cooler than November has been so far this year). After that, the trend reversed. December 2019 was 4 degrees warmer than average and January 2020 was a whopping 6.9 degrees warmer than average. February was only 0.7 degrees warmer than average.” says Chief Meteorologist Bill Steffen.
The reason for the bust in snow totals had everything to do with the lack of lake-effect snow. West Michigan saw the same number of storm systems as usual, but lacked cold enough air to trigger many big lake-effect events. This robbed our side of the state of several inches of snow.
WHAT WE EXPECT THIS YEAR
This year looks to continue with a mild start. November has been one of our sunniest on record and is 5 degrees warmer than usual so far this month. A strong polar vortex has formed and looks to stay locked far to the north, keeping any very cold air intrusions north of West Michigan through the start of December.
La Nina years typically give us above-average precipitation. The biggest question is whether it will be in the form of snow. Often, La Nina years dish out a lot of cold and snow in February, which isn’t usually our snowiest month. We also expect that to be the case this year.
There is a good chance we will see one major cold air outbreak toward the end of December and the start of January as the polar vortex wobbles or weakens (which allows it to swing south into latitudes like ours). There is also a good chance we will see a big mid-winter thaw.
Expect about two systems with a wintry mix of some sort. Hopefully we will be spared any major ice storms, but the La Nina storm track does put West Michigan close to the rain/snow/ice line occasionally.
“Snow enthusiasts rejoice! I think Northern Michigan, especially the U.P. will have a great snowy, cold winter. They’re already off to a great start in October.” says Meteorologist Matt Kirkwood. You can follow snow conditions through the winter with Matt’s weekly Snow Conditions Report.
Expect winter to linger this year into March and April. We are not expecting any quick warmups into spring.
Each of us at Storm Team 8 did our own research. Above are all the things we each agree will likely happen this winter. One thing we did disagree on was the amount of snow each of our main climate stations will see. Bill Steffen and Ellen Bacca both forecast slightly less snow than usual. Matt Kirkwood, Terri DeBoer, and Emily Schuitema all forecast slightly more snow for the winter.
There now is a fun competition brewing between Team Daybreak and Team Nightside. The prize is a batch of Emily Schuitema’s mom’s famous molasses cookies.
Here are each of the snow forecasts from the members of Storm Team 8 (click through to see each meteorologists’ predictions):
You and your kids can help gather snowfall data from home this winter. Here on woodtv.com, we’ve got a handy guide for measuring snow and sending your information to Storm Team 8 Forecast.