A storm system developing over the US plains will bring an area of snow over the eastern Dakotas and NW Minnesota Monday, which will spread into southeast MB Monday afternoon into Monday night. Snow may be heavy at times especially south of the US border and east of the RRV where amounts of 10 cm or more are possible. In fact, the US National Weather Service in Grand Forks has issued a winter weather advisory for areas south and east of Grand Forks into NW Minnesota where 3 to 5 inches of snow is forecast (8 to 13 cm). UPDATE: Winter weather advisory has been expanded northwest to include Grand Forks and areas up to the Canadian border.
(Map showing 24hr snowfall amounts from RGEM between 6 am Monday and 6 am Tuesday. Dark green area is 10-15 cm over Lake of the Woods with sharply lower amounts west of the RRV. Light green line is 2.5 cm. Model output from 00z Feb 20 RGEM run)
In southern MB, there will be a sharp western edge to this area of snow, with little or no snow falling west of the RRV. In Winnipeg, snow is expected to begin late in the afternoon, with 2-5 cm possible through Monday night. Depending on where this western edge sets up, Winnipeg may get brushed with just a dusting of snow (more likely), or heavier amounts of 5-10 cm (less likely). Fortunately, winds with this system will be light and temperatures will be near the freezing mark so snow will be wet (even possibly beginning as rain at first) with little in the way of blowing or drifting. However, the snow may be heavy at times, especially south and east of Winnipeg with visibilities reduced to 500 metres or less. This will create locally poor travelling conditions and slick road conditions at times over the southern RRV and SE MB by Monday evening including Hwys 1, 59 and 75 south and east of Winnipeg.. an issue for residents heading back from the US or NW Ontario from the long holiday weekend.