Napa, CA Weather OverviewScoresFors & AgainstsWeatherPhotos Average Temperature Jan 57 °F14 °C Feb 53 °F12 °C Mar 59 °F15 °C Apr 66 °F19 °C May 66 °F19 °C Jun 77 °F25 °C Jul 77 °F25 °C Aug 79 °F26 °C Sep 78 °F26 °C Oct 73 °F23 °C Nov 68 °F20 °C Dec 54 °F12 °C Humidity Jan 77% Feb 76% Mar 72% Apr 72% May 75% Jun 64% Jul 70% Aug 71% Sep 61% Oct 35% Nov 60% Dec 84% Rain Jan 82mm Feb 141mm Mar 64mm Apr 14mm May 40mm Jun 5mm Jul 6mm Aug 4mm Sep 10mm Oct 4mm Nov 23mm Dec 87mm Clouds Jan 48% Feb 44% Mar 56% Apr 34% May 37% Jun 18% Jul 14% Aug 15% Sep 7% Oct 3% Nov 12% Dec 74% Air quality US AQI Jan 50 Feb 41 Mar 35 Apr 36 May 34 Jun 36 Jul 43 Aug 48 Sep 31 Oct 47 Nov 51 Dec 65 Sun Jan 2UVI Feb 3UVI Mar 4UVI Apr 7UVI May 7UVI Jun 9UVI Jul 10UVI Aug 9UVI Sep 7UVI Oct 5UVI Nov 3UVI Dec 2UVI
