Thursday, February 07, 2008

Another Arctic blast this weekend..

Another blast of Arctic air will be flooding into Southern Manitoba, unfortunately just in time for the weekend. A strong Arctic high over the Yukon will build southward into the Prairies on Friday, driving frigid air across Alberta and Saskatchewan. Strong northwest winds will push the leading edge of this Arctic airmass into southwestern MB late Friday reaching Winnipeg and the Red River valley Friday night. The cold front will be accompanied by some light snow with 1-2 cm possible Friday night. The strong northwest winds and falling temperatures will combine with any loose snow to give extensive drifting and blowing snow Friday night into early Saturday morning, with poor visibilities likely in open areas. This situation is similar to one early last week that brought a few hours of blizzard conditions to southern MB, and led to numerous highway closures. The extent and duration of poor visibilities will be determined by the amount of new snow, if any, that falls Friday night. Note that poor visibilities in blowing snow will be widespread across southern SK Friday as the cold air and strong winds move in.

Conditions will be improving across the Red River valley for Saturday with clearing skies, however brisk northwest winds and cold temperatures will produce high windchill values. Sunday will see lighter winds and below normal temperatures under the Arctic ridge. Temperatures are expected to slowly moderate next week as the Arctic airmass moves east allowing periodic clipper systems to move across the Prairies.

1 comment:

  1. This Arctic front going through tonight may have a little more punch than first thought. Latest forecasts show a little more snow developing tonight over the Red River valley, perhaps 3 to 5 cm instead of the 1 or 2 initially expected. Latest radar showing a band of snow over western SK west of the cold front, resulting in zero visibilities in snow and blowing snow over Kindersley.

    This Arctic cold front will push steadily eastward today reaching Winnipeg around 3 am or so tonight, with blizzard conditions developing behind the front and continuing into Saturday morning depending on how much new snow falls. However, even with minimal snowfall, there will be several hours of poor visibilities in blowing and drifting snow due to northwest winds of 50 gusting 70 km/h developing overnight. As a result, expect poor travelling conditions Saturday across the Red River valley with the possibility of some road closures of major routes like the TransCanada and Hwy 75.