Early snowfall hits Canada and the US

  • Temperatures at Calgary International Airport from Sunday 7th to Friday 12th September. The sharp temperature drop on Monday marks the arrival of the snow Image: MeteoGroup

    A Calgary garden draped in a thick mantle of snow on September 8th 2014. Image: "Summer in Calgary" by davebloggs007, via Flickr Creative Commons.

    Map depicting snow reports across the NWS Rapid City forecast area, which primarily covers western South Dakota and north-east Wyoming. Image: NOAA.

  • Early snowfall hits Canada and the US
    13.09.2014 14:07

    The UK saw the settled theme prevail this week thanks to an area of high pressure, with many areas enjoying some early autumn sunshine and temperatures into the low 20s degrees Celsius. Across the Atlantic, however, parts of Canada and the USA saw an early blast of winter as heavy snowfalls and low temperatures gripped the region.

    On Monday, the Canadian province of Alberta saw an active cold front sweep through from the Arctic, bringing a dramatic drop in temperature. In Calgary, Alberta’s largest city, the arrival of the front was marked by a transition from rain to heavy snow through the morning, giving accumulations of 11.8cm at the International Airport. Temperatures in Calgary struggled to rise much above freezing through Monday afternoon, a stark contrast to the summery 25C recorded just a day earlier. Another round of snow struck the city on Tuesday and Wednesday, bringing the three day total at the airport to 28.2cm. Thousands of trees, which were still full of leaves, collapsed under the weight of the heavy wet snow, cutting power to 30,000 homes and leading to significant traffic disruption. September snow is not an unusual occurrence in Calgary; indeed the city has recorded snow every month of the year. On average, however, the city sees a total of 4cm in September, which normally results from one or two events late in the month. Only 8 September snow events have produced more than 20cm since records began in 1880.

    Snow was also reported across 6 US states as the front continued southwards, with early snow records set in some locations. 1.6 inches of snow was recorded by the National Weather Service in Rapid City, South Dakota on Thursday morning, the earliest ever recorded in the city since records began in 1888, while the high temperature of 3C was a record low maximum for the date. A snow depth of 7 inches was recorded at nearby Mount Rushmore, while an estimated 18 inches fell in Wyoming’s Bighorn Mountains.

    Temperatures across the region have already begun to recover with the eastward shift of the Arctic airmass, and highs of 20-23C are forecast in Calgary through much of next week. Power in the city was mostly restored as of Thursday, although the cleanup operation is expected to take weeks.

    By: Billy Payne