A Legacy of Snow
Calgary International Airport reported 11.8 centimeters (about 4.6 inches) of snow on Monday, another 1.3 centimeters (about 0.5 inches) on Tuesday and then 15.1 centimeters (about 5.9 inches) on Wednesday.
Multiple rounds of snow were reported from Monday to Wednesday, across a large part of Canada's Alberta province, including its largest city, Calgary. On Tuesday, a section of the Going-to-the-Sun Road in Glacier National Park over Logan Pass was closed by park officials due to snow.
Great Falls, Montana, witnessed its earliest first snow of the season in 22 years on Tuesday night. Only six other years, since 1892, witnessed snow before September 9 in Great Falls, according to the National Weather Service. Though it was shocking to many, it wasn't the city's earliest late-summer snowfall. Calgary recorded 11.7 centimeters (just under 5 inches) of snow on September 8 in 1921, according to Environment Canada statistics.
The earliest single-day snowfall of 10 centimeters (4 inches) or more was received on September 6, 1972, but Calgary had a two-day total of 10.4 centimeters on August, 25-26, 1900. It even snowed in Calgary once in July, when 0.3 centimeter (0.1 inch) fell on July 23, 1918.
September has, on average, 1-2 days of measurable snow in Calgary. On average, only one September day every three years sees at least 5 centimeters (just under 2 inches) of snow. Calgary's three-day total of 28.2 centimeters (about 11.1 inches) is on par with average snowfall for September, October and November, combined (31 centimeters), according to Environment Canada, the country's equivalent of the National Weather Service.
This week's snow was an attention-grabber, especially coming so early in the month and just a day after Sunday's high of 78 degrees Fahrenheit. Some of that snow spilled over the international border, delivering over a foot of snow to the Bighorn Mountains west of Sheridan, Wyoming, and the earliest measurable snowfall on record in Rapid City, South Dakota. Over a foot of snow was reported in parts of Wyoming Thursday as an unusually early snowstorm spread southeastward with 12 days of summer still remaining.
The season's first frost and freeze is also on the way for parts of the Rockies, Plains, Northwest, and Upper Midwest this week.
Summer Snow!
Thursday morning brought the earliest measurable snow on record to Rapid City, South Dakota. Snow piled up to 8 inches deep in the Black Hills near Custer, South Dakota. Farther west, the snow was even heavier in parts of northern Wyoming, where up to 14 inches fell near the town of Story in Sheridan County. Broken branches, downed trees and power outages resulted from the heavy, wet snow in that area.
picture courtesy - Blue Pueblo