Napa Weather in December
Average highs run from 61°F on December 1 to 58°F on December 31, and lows from 41°F to 39°F. Normal precipitation for the month is 5.53 in over about 12 wet days.
December day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
December at a glance
- Average high
- 59°F
- Average low
- 40°F
- Precipitation
- 5.53 in
- Record high
- 78°FDec 7, 2020
- Record low
- 16°FDec 5, 2013
- Chance of a freeze
- 78%
- Daylight
- 9 h 42 min to 9 h 33 min
- Cloud cover
- 58%
- Humidity
- 81%
- Dew point
- 39°F
- Wind
- 6.7 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| Dec 1 | 61°F | 41°F | 69°F 2011 | 20°F 2007 | 35% |
| Dec 2 | 61°F | 41°F | 75°F 2011 | 24°F 2004 | 35% |
| Dec 3 | 60°F | 41°F | 67°F 2020 | 28°F 2004 | 36% |
| Dec 4 | 60°F | 41°F | 70°F 2020 | 22°F 2004 | 36% |
| Dec 5 | 60°F | 40°F | 67°F 2023 | 16°F 2013 | 36% |
| Dec 6 | 60°F | 40°F | 67°F 2024 | 20°F 2013 | 36% |
| Dec 7 | 59°F | 40°F | 78°F 2020 | 22°F 2009 | 37% |
| Dec 8 | 59°F | 40°F | 71°F 2020 | 19°F 2009 | 37% |
| Dec 9 | 59°F | 40°F | 70°F 2012 | 19°F 2013 | 37% |
| Dec 10 | 59°F | 40°F | 66°F 2017 | 21°F 2013 | 37% |
| Dec 11 | 59°F | 40°F | 66°F 2017 | 25°F 2013 | 37% |
| Dec 12 | 59°F | 40°F | 64°F 2018 | 26°F 2013 | 37% |
| Dec 13 | 59°F | 40°F | 62°F 2023 | 24°F 2007 | 37% |
| Dec 14 | 58°F | 40°F | 63°F 2017 | 24°F 2007 | 38% |
| Dec 15 | 58°F | 40°F | 66°F 2023 | 26°F 2005 | 38% |
| Dec 16 | 58°F | 40°F | 70°F 2023 | 28°F 2005 | 38% |
| Dec 17 | 58°F | 39°F | 66°F 2000 | 24°F 2008 | 38% |
| Dec 18 | 58°F | 39°F | 63°F 2017 | 21°F 2006 | 37% |
| Dec 19 | 58°F | 39°F | 78°F 1999 | 21°F 2006 | 37% |
| Dec 20 | 58°F | 39°F | 67°F 1999 | 25°F 2008 | 38% |
| Dec 21 | 58°F | 39°F | 71°F 1999 | 21°F 1998 | 38% |
| Dec 22 | 58°F | 39°F | 68°F 1999 | 19°F 1998 | 38% |
| Dec 23 | 58°F | 39°F | 66°F 2004 | 20°F 2011 | 37% |
| Dec 24 | 58°F | 39°F | 65°F 2013 | 19°F 1998 | 38% |
| Dec 25 | 58°F | 39°F | 65°F 2013 | 24°F 1998 | 38% |
| Dec 26 | 58°F | 39°F | 67°F 2013 | 24°F 2011 | 38% |
| Dec 27 | 58°F | 39°F | 67°F 1999 | 25°F 2015 | 38% |
| Dec 28 | 58°F | 39°F | 64°F 1999 | 24°F 2013 | 38% |
| Dec 29 | 58°F | 39°F | 64°F 2013 | 25°F 2015 | 38% |
| Dec 30 | 58°F | 39°F | 63°F 2013 | 26°F 2015 | 38% |
| Dec 31 | 58°F | 39°F | 64°F 2020 | 24°F 2015 | 38% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (PST).
- December 1
- sunrise 7:07 AM, sunset 4:49 PM
- December 31
- sunrise 7:26 AM, sunset 4:59 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00046074 (Napa State Hospital), public domain. Records: NOAA GHCN-Daily, station USW00093227, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.