Olympia, WA Weather OverviewScoresFors & AgainstsWeatherPhotos Average Temperature Jan 46 °F8 °C Feb 41 °F5 °C Mar 54 °F12 °C Apr 57 °F14 °C May 66 °F19 °C Jun 68 °F20 °C Jul 73 °F23 °C Aug 75 °F24 °C Sep 68 °F20 °C Oct 57 °F14 °C Nov 51 °F11 °C Dec 46 °F8 °C Humidity Jan 87% Feb 85% Mar 70% Apr 78% May 73% Jun 71% Jul 71% Aug 76% Sep 84% Oct 79% Nov 83% Dec 91% Rain Jan 63mm Feb 57mm Mar 28mm Apr 48mm May 17mm Jun 14mm Jul 18mm Aug 20mm Sep 70mm Oct 56mm Nov 30mm Dec 79mm Clouds Jan 75% Feb 69% Mar 42% Apr 70% May 47% Jun 41% Jul 43% Aug 44% Sep 51% Oct 52% Nov 68% Dec 82% Air quality US AQI Jan 22 Feb 18 Mar 16 Apr 12 May 14 Jun 12 Jul 15 Aug 23 Sep 17 Oct 30 Nov 31 Dec 33 Sun Jan 1UVI Feb 1UVI Mar 3UVI Apr 4UVI May 5UVI Jun 6UVI Jul 6UVI Aug 6UVI Sep 4UVI Oct 3UVI Nov 1UVI Dec 1UVI