Daylight saving time has ended, the heat of summer is gone, and the inevitable chill has been creeping across the country. It’s barely November but some locations have already seen their first snowfall. In the Rockies, a good early season snowpack helped the first ski area in the country open on October 13 while this year’s first snowstorm in Deadwood, SD dumped 4 feet of snow. Snow could be just around the corner for other parts of the U.S. shortly.
The date of first snowfall is dependent on local weather conditions. In 1952, New York City saw its first snow fall in Central Park on October 21, the earliest ever recorded for the city. On the other hand, Chicago had to wait until December 20 last season before it saw white due to persistent warm temperatures.
Although natural variations in the weather patterns have the greatest effect on snow totals in a given year, the increase in global temperatures is creating some overall trends. This past century has seen a decrease in overall snow cover in the Northern Hemisphere and a shrinking snowpack across the West. The main drivers are more snow falling as rain and snow melting earlier in the season. At the same time, very snowy winters (winters with a heavy amount of accumulation) have been decreasing in frequency in most parts of the country over the past two decades. There is one exception: the Northeast has maintained roughly the same number of very snowy winters throughout the period between 1900-2007.
While no clear trend has emerged in the frequency of snowstorms in the U.S., there is a lot of current research looking into the effects of climate change on the jet stream and extreme weather – which could have an effect on storm tracks and snowfall trends.
You can watch and listen here as NCDC's Jay Lawrimore and WBOC's Dan Satterfield give their explanation to the connection between climate change and snowstorms.