Napa, CA weather in January
Expect cool weather with frequent rain in Napa in January, with highs near 59°F and lows near 40°F. Rain falls on about 12 days. It is one of the coolest months in Napa.
- Normal high
- 59°F
- Normal low
- 40°F
- Wet days
- 12
- 5.0 in total
- Muggy days
- 0
- dew point 65°F+
How January changes from start to finish
| January 1 | January 31 | |
|---|---|---|
| Normal high | 58°F | 61°F |
| Normal low | 39°F | 41°F |
| Chance of a wet day | 38% | 38% |
| Sunrise / sunset | 7:26 am / 4:59 pm | 7:14 am / 5:30 pm |
| Daylight | 9.6 h | 10.3 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Pacific Time).
A typical January day
- 6 am42°Fdew point 39°F
- 9 am45°Fdew point 41°F
- Noon53°Fdew point 43°F
- 3 pm56°Fdew point 43°F
- 6 pm49°Fdew point 43°F
- 9 pm46°Fdew point 42°F
NOAA hourly normals (local standard time) from Travis AFB (19 mi away); average wind 7 mph; clear or few clouds in 47% of daytime hours, mostly cloudy or overcast in 47%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F5 of 31
- Hot dayshigh 90°F or more0 of 31
- Muggy daysdaily mean dew point 65°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow12 of 31
- Notable rainat least 0.10 in9 of 31
- Freezing nightslow 32°F or below5 of 31
Average days per January, counted from daily records for each year 1991-2020.
Rain in January
Normal precipitation is 5.0 in; a dry January brings about 2.4 in and a wet one about 8.0 in (25th and 75th percentiles). About 4 days bring half an inch or more, and about 2 an inch or more. Snow is very rare.
How January varies from year to year
- Warmest January, 1991-20202014: average high 67°F
- Coolest January2008: average high 55°F
- Wettest January1995: 13.7 in
- Driest January2007: 0.4 in
- Highest reading80°F (January 1, 1996)
- Lowest reading23°F (January 17, 2012)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
January compared with December and February
| December | January | February | |
|---|---|---|---|
| Normal high | 59°F | 59°F | 63°F |
| Normal low | 40°F | 40°F | 42°F |
| Wet days | 12 | 12 | 11 |
| Comfortable days | 3 | 5 | 12 |
| Daylight | 9.6 h | 9.8 h | 10.8 h |
Highs change by 0°F from December and +4°F into February.
Nearby alternatives in January
- Drier: Yosemite Valley, CA152 mi · high 48°F · 9 wet days
- Cooler: South Lake Tahoe, CA132 mi · high 43°F · 10 wet days
How Napa ranks in January
- Normal high115th warmest of 378 cities; 37th of 60 in California
- Wet days310th driest of 378
- Comfortable days131st most of 339
What to pack for Napa in January
- A warm jacket – lows near 40°F, highs near 59°F
- A rain jacket or umbrella – rain on about 12 days
Heating and cooling
January has 485 heating degree days and 0 cooling degree days (base 65°F), 16% of the year's total heating and cooling demand.
Questions
How cold is Napa in January?
The normal high is 59°F and the normal low is 40°F. From 1991 to 2020 the coldest January reading was 23°F (January 17, 2012).
Does it rain a lot in Napa in January?
About 12 days in January have at least 0.01 in of precipitation, and the normal total is 5.0 in. The wettest January in 1991-2020 was in 1995 (13.7 in); the driest was in 2007 (0.4 in).
Does it snow in Napa in January?
Snow is very rare: the 1991-2020 normal for January rounds to 0.0 in.
Is January a good time to visit Napa?
January ranks 11th of 12 months on our comfort score for Napa (46 out of 100). It has about 5 comfortable days. The best month is May.
Where the numbers come from
- Temperature, rain, snowfall and frost dates: Napa State Hospital (USC00046074), 1.8 mi SE of the city center, 35 ft . NOAA normals and daily records, 1991-2020.
- Snow depth: Fairfield (USC00042934), 12 mi E of the city center, 40 ft . NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour and cloud cover: Travis AFB (USW00023202), 19 mi E of the city center, 59 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Napa County Airport (724955-93227), 6.2 mi S of the city center, 15 ft . Hourly observations, 1991-2020.