- y( q" U1 x' IA very cold Arctic airmass and winds of 15 to 20 km/h will generate wind chill values below minus 40 across much of Alberta tonight. Conditions will improve somewhat by Sunday afternoon as temperatures rise. 1 I4 r% G2 D( \1 F. x, ~8 NAt these extreme wind chill values frostbite on exposed skin may occur in less than 10 minutes. & p2 j: { Q6 r) `