October isn’t generally a month known for its snowfall totals or winter storms. However, October 2020 will be a different story. This month is already on-track for historic snowfall, according to national weather agencies. Record-setting snow totals have been recorded across the Rockies, the Northern Plains, the Upper Midwest, and even into New England.
This is due, in large part, to La Nina conditions over the Pacific driving cold, wet air north into Canada and along the jet stream. From there, the jet stream makes a swooping motion over the US, bringing wet, cold conditions from West to East. Great Falls, Montana, saw the highest snowfall totals of October from Friday to Monday: 13.8 inches.
Great Falls saw several records get set over the weekend. The greatest single-day snowfall in October came on Sunday, to the tune of 8.2 inches. The earliest-in-season ten-inch snow depth was hit Monday, beating the previous date of November 9, 2012. Monday also marked the greatest snow depth ever recorded in the region in October.
This might sound familiar to people in Montana. In 2019, a freak September snowstorm got the cold season started with a bang, bringing up to four feet of snow to parts of the state. This incident resulted in an emergency declaration from the governor, Steve Bullock, and kicked off an October full of snowfall.
Snow Blankets Northern US
Outside of Montana, snow blanketed much of the Northern US over the weekend. On Sunday, Des Moines saw its earliest accumulation of an inch of snow since 1885, breaking an over 100-year-old record.
Monday, parts of Iowa were buffeted by a snowstorm that brought between six and nine inches to some parts of Des Moines. In Ankeny, Iowa, Monday has the highest-ever recorded snowfall of an October day.
Likewise, a Monday snowstorm in Cedar Rapids quickly became the most-damaging single-day thunderstorm in the US since 1980. Uprooted trees, fallen power lines and a scattering of snow throughout the region shocked residents. Many noted that they expected heavy snowfall this year, but maybe not so early in the season.
Why so Much Snow?
This season’s high snowfall amounts can be traced back to the jet stream and La Nina. A jet stream pattern with a dome of high pressure is currently bringing the moist, cold conditions over the Northern US, and threatens to even push some snow into parts of the South.
Needless to say, we’re in for an active winter, full of storms and snow.