The start of this week will be warm and windy – with daytime highs across southern Alberta sitting in the low to high 20s. Strong west wind will continue to flow over the Rockies throughout the day. As of 5 a.m. Monday, sustained wind speeds around 50 km/h with gusts near 70 km/h had been observed in Pincher Creek and by 7:30 a.m. gusts over 60 km/h had been recorded in Lethbridge. Calgary will see sustained wind speeds of 20 to 40 km/h on Monday with gusts around 40 to 60 km/h. That west wind is helping to drive temperatures up across southern Alberta. As of 7 a.m. Monday, it was 15 C in Calgary and 18 C in Lethbridge – compared to a normal morning low in Calgary of 0 C. Monday will be the warmest day of this week with a forecast high in Calgary of 23 C and highs up to 27 C in Medicine Hat. Daytime highs will moderate slightly by the middle of the week before dropping significantly at the start of the Thanksgiving weekend. A shift in the upper patterns will drag the mid-latitude jet stream south and introduce both cold air and heightened instability by the end of the week. Rain will transition to mixed precipitation and snow across southern British Columbia and central and southern Alberta – including the Rockies – which could impact travel over the Thanksgiving weekend. Strong north wind will precede that precipitation on the weekend potentially causing road conditions to rapidly deteriorate. Daytime highs will drop from 17 C to 3 C from Friday to Saturday and peak at 2 C on Sunday. Overnight lows in Calgary will drop below freezing on Saturday and Sunday.
