About three weeks ago, I "fearlessly" gave my winter forecast for 2012-13 on Newschannel 3. It slipped my mind to put the forecast in writing, here on my blog, until earlier this week.
First, it appears that a weak El Nino will be occurring for the next few months, and that could have an impact on our weather. Historically, El Ninos help keep the northern branch of the jet stream to our north during the winter months. The result is less than average snowfall, and that's what we've had more often than not during the past few weak El Ninos.
That's why I'm predicting that overall, we'll have about 10 to 20 percent less snowfall than what we have in a typical winter. For locations along and just east of U.S.131 -- Kalamazoo, Grand Rapids, Three Rivers, for examples, we'll get between 55 and 60" of snowfall this season; typically, about 70 to 75" falls in this area.
Well east of U.S. 131, in Battle Creek, Coldwater, Marshall, and Hastings, for examples, you'll see between 40 and 50" of snowfall instead of the typical 50 to 60". West of U.S. 131, the lake effect snow belt, will also see less snow. Locations like Paw Paw, Allegan, Saugatuck, Holland, and Muskegon will see between 75 and 90" of snowfall, where normally there would be between 90 and 110".
Research into the past five or so weak El Nino winters shows that in West Michigan, the snowfall gets off to a slow start, with less than average snowfall in November and December, hits its stride in January, then tapers off again in February and March. Accordingly, I'm predicting we'll see about 4" of snow in November (average is 8"), 10" in December (18"), 25" in January (22"), 10" in February (13"), 8" in March (10"), and 1" in April (3").
Additionally, I'm predicting our first areawide snowfall of 2" or greater will occur sometime in the last week of November or the first week of December. We'll have to wait a while for our first areawide, non lake effect significant snowfall (6" or more); I predict that will happen sometime during the last two weeks of January.
Regarding temperatures, there don't seem to be any indicators from past weak El Nino winters for temperature trends; nothing that would point to an unusually warm or unusually cold season. However, because the northern branch of the jet stream often spends more time to our north in an El Nino winter compared to a non-El Nino influenced season, I wouldn't be surprised if overall, temperatures run a little warmer than average.
I'll check back on the forecast from time to time over the next few months to see how it's faring. My fingers are crossed!