January weather forecastFairfax, CA
January
Weather in January
January is a moderate winter month in Fairfax, California, with an average temperature varying between 46.6°F (8.1°C) and 55.9°F (13.3°C).Temperature
In January, Fairfax experiences a minor shift in meteorological conditions with average high-temperatures marked at a refreshing 55.9°F (13.3°C), closely mirroring the climate in December. Fairfax sees an average low-temperature of 46.6°F (8.1°C) during January.Humidity
In January, the average relative humidity is 74%.Rainfall
In Fairfax, in January, during 10.3 rainfall days, 2.64" (67mm) of precipitation is typically accumulated. In Fairfax, during the entire year, the rain falls for 80.3 days and collects up to 15.98" (406mm) of precipitation.Snowfall
In Fairfax, snow does not fall in January through November.Daylight
In Fairfax, the average length of the day in January is 9h and 53min.On the first day of January, sunrise is at 7:26 am and sunset at 5:01 pm. On the last day of the month, sunrise is at 7:15 am and sunset at 5:31 pm PST.
Sunshine
In Fairfax, California, the average sunshine in January is 5.7h.UV index
In January, the average daily maximum UV index is 4. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for ordinary individuals.Note: The daily high UV index of 4 during January translates into the following recommendations:
Act with care - The need to guard against sun damage is communicated. For health reasons, it's advisable to reduce direct sun exposure during peak hours around midday. Arm yourself against UV rays' harm with protective apparel and UV-filtering shades.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Fairfax, CA
- Average high temperature in January: 55.9°F
The warmest month (with the highest average high temperature) is September (70.9°F).
The month with the lowest average high temperature is December (55.2°F).
- Average low temperature in January: 46.6°F
The month with the highest average low temperature is September (56.3°F).
The coldest month (with the lowest average low temperature) is December (46°F).
Average pressure in January
Fairfax, CA
- Average pressure in January: 30.13"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in January
Fairfax, CA
- Average wind speed in January: 6.5mph
The windiest months (with the highest average wind speed) are April and May (8.3mph).
The calmest month (with the lowest average wind speed) is November (5.9mph).
Average humidity in January
Fairfax, CA
- Average humidity in January: 74%
The month with the highest relative humidity is August (78%).
The month with the lowest relative humidity is October (69%).
Average rainfall in January
Fairfax, CA
- Average rainfall in January: 2.64"
The wettest month (with the highest rainfall) is February (3.43").
The driest months (with the least rainfall) are July and August (0.08").
Average rainfall days in January
Fairfax, CA
- Average rainfall days in January: 10.3 days
The month with the highest number of rainy days is March (12.8 days).
The month with the least rainy days is July (2.3 days).
Average snowfall days in January
Fairfax, CA
- Average snowfall days in January: 0 days
The month with the highest number of snowfall days is December (0.1 days).
The months with the least snowfall days are January, February, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in January /
Average sunshine in January
Fairfax, CA
- Average daylight in January: 9h and 54min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in January: 5h and 42min
The month with the most sunshine is July (Average sunshine: 11h and 12min).
The month with the least sunshine is December (Average sunshine: 5h and 36min).
Average sunshine days in January
Fairfax, CA
- Average sunshine days in January: 20.1 days
The months with the most sunshine days are June and July (24.8 days).
The month with the least sunshine days is March (16.6 days).
Average UV index in January
Fairfax, CA
- Average UV index in January: 4
The months with the highest UV index are June, July, August and September (UV index 5).
The months with the lowest UV index are February, November and December (UV index 3).
Average cloud cover in January
Fairfax, CA
- Average cloud cover in January: 36
The month with the most cloud cover is March (Cloud cover 39).
The month with the least cloud cover is September (Cloud cover 19).
Average visibility in January
Fairfax, CA
- Average visibility in January: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





