Lethbridge Weather OverviewScoresFors & AgainstsWeatherPhotos Average Temperature Jan 36 °F2 °C Feb 1 °F-18 °C Mar 36 °F2 °C Apr 51 °F11 °C May 57 °F14 °C Jun 67 °F20 °C Jul 72 °F22 °C Aug 73 °F23 °C Sep 64 °F18 °C Oct 45 °F7 °C Nov 37 °F3 °C Dec 32 °F0 °C Humidity Jan 63% Feb 58% Mar 67% Apr 52% May 63% Jun 61% Jul 56% Aug 62% Sep 65% Oct 67% Nov 69% Dec 70% Rain Jan 12mm Feb 16mm Mar 9mm Apr 20mm May 32mm Jun 86mm Jul 31mm Aug 30mm Sep 36mm Oct 17mm Nov 23mm Dec 9mm Clouds Jan 45% Feb 60% Mar 32% Apr 44% May 52% Jun 32% Jul 22% Aug 32% Sep 46% Oct 43% Nov 56% Dec 46% Air quality US AQI Jan 14 Feb 19 Mar 23 Apr 16 May 22 Jun 14 Jul 25 Aug 41 Sep 22 Oct 17 Nov 18 Dec 11 Sun Jan 1UVI Feb 1UVI Mar 3UVI Apr 4UVI May 5UVI Jun 6UVI Jul 7UVI Aug 6UVI Sep 4UVI Oct 2UVI Nov 1UVI Dec 1UVI