% n/ r% E2 [9 ~+ l0 x7 v' Q$ vA 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 A# \( h5 G6 i4 |, N- vAt these extreme wind chill values frostbite on exposed skin may occur in less than 10 minutes. ; I. ?0 P9 y& J1 k B) l: M( Y& s/ C