Napa Valley weather in December
Temperature, rain and sunshine in December: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in December
Fair
Best time to visit: April – October
What is the weather like in Napa Valley in December?
In December, Napa Valley is cool: daytime highs average 14 °C, and nights cool down to about 5 °C. Expect around 4 hours of sunshine a day. Rain is frequent, with about 10 rainy days and 114 mm in total. All in all, December is a so-so month for a holiday in Napa Valley.
December compared
How the weather changes from November to January. Tap a month to open it.
| NovemberNov | DecemberDec | JanuaryJan | |
|---|---|---|---|
| Score | 84 | 55 | 58 |
| Day | 18° | 14° | 14° |
| Night | 8° | 5° | 5° |
| Sun | 6 h | 4 h | 4 h |
| Rain days | 6 | 10 | 9 |
More details for December
- Daylight
- 9 h 31 min07:19 – 16:50
- UV index
- 2 · lowclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 12 km/haverage daily peakAll months
- Cloud cover
- 61 %on averageAll months
- Hot days
- 0 days30 °C or moreAll months
- Time zone
- UTC−8America/Los_Angeles
How the score comes together
- Temperatureweight 50 %66 %
- Sunshineweight 20 %23 %
- Few rainy daysweight 30 %58 %
Each factor is rated from 0 to 100 % and weighted for the travel style “Nature escape”.
What to pack in December
- A jumper for the evenings
- Rain jacket or umbrella
Napa Valley in December: quick answers
Is Napa Valley hot in December?
No. In December, Napa Valley is cool: daytime highs average 14 °C and nights drop to about 5 °C.
Does it rain much in Napa Valley in December?
Rain is frequent, with about 10 rainy days and 114 mm in total.
Napa Valley month by month
The whole year in Napa ValleyAll destinations: USAWhere to go in December
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences