Vallejo, CA weather in January
January in Vallejo: cool, with frequent rain. Highs 59°F, lows 40°F, rain on about 11 days. It is one of the coolest months in Vallejo.
- Normal high
- 59°F
- Normal low
- 40°F
- Wet days
- 11
- 3.9 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 | 35% | 36% |
| Sunrise / sunset | 7:25 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 (21 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 snow11 of 31
- Notable rainat least 0.10 in8 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 3.9 in; a dry January brings about 1.3 in and a wet one about 6.2 in (25th and 75th percentiles). About 3 days bring half an inch or more, and about 1 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 January2017: 11.5 in
- Driest January2014: 0.08 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 | 10 | 11 | 11 |
| Comfortable days | 3 | 5 | 12 |
| Daylight | 9.6 h | 9.9 h | 10.8 h |
Highs change by 0°F from December and +4°F into February.
Nearby alternatives in January
- Warmer: Santa Maria, CA240 mi · high 65°F · 8 wet days
- Drier: Reno, NV164 mi · high 48°F · 7 wet days
- Cooler: South Lake Tahoe, CA136 mi · high 43°F · 10 wet days
How Vallejo ranks in January
- Normal high116th warmest of 378 cities; 38th of 60 in California
- Wet days291st driest of 378
- Comfortable days132nd most of 339
What to pack for Vallejo in January
- A warm jacket – lows near 40°F, highs near 59°F
- A rain jacket or umbrella – rain on about 11 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 Vallejo 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 Vallejo in January?
About 11 days in January have at least 0.01 in of precipitation, and the normal total is 3.9 in. The wettest January in 1991-2020 was in 2017 (11.5 in); the driest was in 2014 (0.08 in).
Does it snow in Vallejo in January?
Snow is very rare: the 1991-2020 normal for January rounds to 0.0 in.
Is January a good time to visit Vallejo?
January ranks 11th of 12 months on our comfort score for Vallejo (47 out of 100). It has about 5 comfortable days. The best month is May.
Where the numbers come from
- Temperature: Napa State Hospital (USC00046074), 12 mi N of the city center, 35 ft . NOAA normals and daily records, 1991-2020.
- Rain: Martinez WTP (USC00045378), 10 mi SE of the city center, 40 ft . NOAA normals and daily records, 1991-2020.
- Snowfall and snow depth: Fairfield (USC00042934), 16 mi NE of the city center, 40 ft . NOAA normals and daily records, 1991-2020.
- Frost dates: Napa Co Airport (USW00093227), 7.5 mi NNW of the city center, 14 ft (55 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour and cloud cover: Travis AFB (USW00023202), 21 mi ENE of the city center, 59 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Napa County Airport (724955-93227), 7.3 mi N of the city center, 15 ft (54 ft lower than the city). Hourly observations, 1991-2020.