January weather forecastSan Jose, CA
January
Weather in January
San Jose weather in January displays the typical characteristics of the Californian winter. Dry cool air dominates the region, with relatively low temperatures and cloud cover. The city experiences wind speeds of 4.6mph (7.4km/h) on average, which can peak at 5.2mph (8.4km/h) and gust up to 7.5mph (12.1km/h), creating a cool breeze throughout the city. Showers are relatively frequent, making it one of the wetter months of the year. January sets the year off with a mild and gentle pace.Temperature
San Jose experiences a minor change to a still moderate 58.1°F (14.5°C) in average high-temperature during January, closely reflecting December. Nighttime temperature in San Jose experiences an average drop to a chilly 43.3°F (6.3°C) in January.Humidity
In January, the average relative humidity is 72%.Rainfall
In San Jose, in January, it is raining for 6.3 days, with typically 0.63" (16mm) of accumulated precipitation. Throughout the year, there are 51.5 rainfall days, and 4.06" (103mm) of precipitation is accumulated.Daylight
In January, the average length of the day is 9h and 56min.On the first day of the month, sunrise is at 7:21 am and sunset at 5:00 pm. On the last day of January, sunrise is at 7:11 am and sunset at 5:30 pm PST.
Sunshine
The average sunshine in January is 6.3h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 3. A UV Index value of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV radiation for the average person.Note: The maximum daily UV index of 3 during January translates into the following directions:
Exercise prudence. Persons with fair skin could be burned in under 30 minutes. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
San Jose, CA
- Average high temperature in January: 58.1°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is December (56.5°F).
- Average low temperature in January: 43.3°F
The month with the highest average low temperature is August (56.5°F).
The coldest month (with the lowest average low temperature) is December (43°F).
Average pressure in January
San Jose, 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
San Jose, CA
- Average wind speed in January: 4.6mph
The windiest months (with the highest average wind speed) are April and May (5.8mph).
The calmest months (with the lowest average wind speed) are September and October (4.4mph).
Average humidity in January
San Jose, CA
- Average humidity in January: 72%
The month with the highest relative humidity is March (73%).
The months with the lowest relative humidity are July and September (60%).
Average rainfall in January
San Jose, CA
- Average rainfall in January: 0.63"
The wettest month (with the highest rainfall) is March (0.83").
The driest months (with the least rainfall) are June, July and August (0.04").
Average rainfall days in January
San Jose, CA
- Average rainfall days in January: 6.3 days
The month with the highest number of rainy days is March (9.8 days).
The month with the least rainy days is August (0.4 days).
Average daylight in January /
Average sunshine in January
San Jose, CA
- Average daylight in January: 9h and 54min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in January: 6h and 18min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).
Average sunshine days in January
San Jose, CA
- Average sunshine days in January: 23.3 days
The month with the most sunshine days is August (29.7 days).
The month with the least sunshine days is March (19.5 days).
Average UV index in January
San Jose, CA
- Average UV index in January: 3
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in January
San Jose, CA
- Average cloud cover in January: 30
The month with the most cloud cover is March (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 6).
Average visibility in January
San Jose, 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).
