Pasco, WA Weather OverviewScoresFors & AgainstsWeatherPhotos Average Temperature Jan 39 °F4 °C Feb 28 °F-2 °C Mar 43 °F6 °C Apr 63 °F17 °C May 73 °F23 °C Jun 81 °F27 °C Jul 84 °F29 °C Aug 86 °F30 °C Sep 75 °F24 °C Oct 59 °F15 °C Nov 46 °F8 °C Dec 37 °F3 °C Humidity Jan 80% Feb 81% Mar 75% Apr 53% May 49% Jun 42% Jul 41% Aug 41% Sep 54% Oct 53% Nov 75% Dec 80% Rain Jan 18mm Feb 13mm Mar 11mm Apr 9mm May 11mm Jun 3mm Jul 3mm Aug 5mm Sep 9mm Oct 12mm Nov 6mm Dec 15mm Clouds Jan 77% Feb 82% Mar 36% Apr 44% May 22% Jun 14% Jul 6% Aug 5% Sep 25% Oct 27% Nov 44% Dec 75% Air quality US AQI Jan 25 Feb 20 Mar 15 Apr 12 May 17 Jun 14 Jul 23 Aug 40 Sep 19 Oct 21 Nov 37 Dec 36 Sun Jan 1UVI Feb 2UVI Mar 3UVI Apr 5UVI May 6UVI Jun 8UVI Jul 8UVI Aug 7UVI Sep 5UVI Oct 3UVI Nov 2UVI Dec 1UVI