Heavy lake-effect snow hits Central Michigan
Arctic air flowing over much-warmer-than-average Lake Michigan waters brought bands of lake-effect snow to central Michigan on December 8, causing slippery roads and poor visibility. At 9:30 am, the extreme conditions caused a massive 40 vehicle pile up near Fowlerville, killing three people and injuring 11 others.
According to AccuWeather senior meteorologist, Dave Samuhel, “A burst of snow affected the interstate around or just before the time of the wreck."
Climate change increases the risk of lake-effect snow. As global warming raises water temperatures in the Great Lakes, preventing the formation of winter ice and causing earlier spring melt, lake-effect snow may occur more often and later in the cold season. Historical observations indicate an increase in lake effect snowfall over much of the Midwest, but declines in the frequency of high magnitude snowfall.
Michigan experienced a record-warm fall in 2016, boosting lake temperatures
Warm waters in Lake Michigan enhance the lake-effect process
Lake-effect snow is a product of temperature differences, specifically between Arctic air and the relatively warm lake waters over which that air blows. As Arctic winds blow over warm lake surfaces, the water evaporates into the cold air, causing the air to warm and rise. As the air rises it cools, making it possible for the water to freeze and fall back down as snow.
Warmer water enhances this process. The warmer the water is, the faster the air will rise and the heavier the lake effect snow.
Beyond experiencing record warm heat during the fall of 2016, the Upper Midwest has the fastest warming winters of any region in the country, with average temperatures climbing 1.12°F per decade since 1970.
That regional warming is also driving up the temperatures of the lakes and driving down ice cover. Since the early 1970s, total ice cover in the Great Lakes has declined by 71 percent.