Contents
- Weather in January
- Frequently asked questions
- Average temperature in January
- Average pressure in January
- Average wind speed in January
- Average humidity in January
- Average rainfall in January
- Average rainfall days in January
- Average daylight in January
- Average sunshine in January
- Average sunshine days in January
- Average UV index in January
- Average cloud cover in January
- Average visibility in January
Weather in January
Temperature
As January takes hold, the average high-temperature is a still mild 56.3°F (13.5°C), nearly mirroring that of the previous month. A consistent nighttime average temperature of 47.8°F (8.8°C) is maintained during January.Humidity
In South San Francisco, the average relative humidity in January is 73%.Rainfall
In South San Francisco, in January, it is raining for 7.2 days, with typically 0.51" (13mm) of accumulated precipitation. Throughout the year, in South San Francisco, there are 53.6 rainfall days, and 3.9" (99mm) of precipitation is accumulated.Daylight
In South San Francisco, the average length of the day in January is 9h and 55min.On the first day of January, sunrise is at 7:24 am and sunset at 5:01 pm. On the last day of the month, sunrise is at 7:14 am and sunset at 5:31 pm PST.
Sunshine
In South San Francisco, California, the average sunshine in January is 6h.UV index
In South San Francisco, the average daily maximum UV index in January is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for average individuals.Note: A daily high UV index of 4 in January leads to these guidelines:
Preventative actions are necessary - Recommendations to ward off sunburn are given. The Sun is at its harshest during midday; protect yourself by staying in shaded areas and minimizing exposure. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Frequently asked questions
What is the average January temperature in South San Francisco?
What is the average humidity in January in South San Francisco?
How much does it rain in South San Francisco in January?
How many hours of daylight does South San Francisco have in January?
When are sunrise and sunset in January in South San Francisco?
How many hours of sunshine does South San Francisco have in January?
What is the UV index reading in January in South San Francisco?
Average temperature in January
South San Francisco, CA
- Average high temperature in January: 56.3°F
The warmest month (with the highest average high temperature) is September (70°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in January: 47.8°F
The months with the highest average low temperature are August and September (56.5°F).
The coldest months (with the lowest average low temperature) are January, February and December (47.8°F).
Average pressure in January
South San Francisco, CA
- Average pressure in January: 30.13"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is September (29.92"Hg).
Average wind speed in January
South San Francisco, CA
- Average wind speed in January: 6.6mph
The windiest month (with the highest average wind speed) is April (8.5mph).
The calmest month (with the lowest average wind speed) is September (6.2mph).
Average humidity in January
South San Francisco, CA
- Average humidity in January: 73%
The month with the highest relative humidity is August (78%).
The months with the lowest relative humidity are October and November (71%).
Average rainfall in January
South San Francisco, CA
- Average rainfall in January: 0.51"
The wettest month (with the highest rainfall) is February (0.79").
The driest months (with the least rainfall) are June, July and August (0.04").
Average rainfall days in January
South San Francisco, CA
- Average rainfall days in January: 7.2 days
The month with the highest number of rainy days is March (9.4 days).
The month with the least rainy days is June (1.1 days).
Average daylight in January /
Average sunshine in January
South San Francisco, CA
- Average daylight in January: 9h and 5min
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 0min
The month with the most sunshine is July (Average sunshine: 11h and 42min).
The month with the least sunshine is December (Average sunshine: 5h and 48min).
Average sunshine days in January
South San Francisco, CA
- Average sunshine days in January: 22.7 days
The months with the most sunshine days are June, July and September (26.3 days).
The month with the least sunshine days is March (19.4 days).
Average UV index in January
South San Francisco, 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 and December (UV index 3).
Average cloud cover in January
South San Francisco, CA
- Average cloud cover in January: 33
The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is September (Cloud cover 16).
Average visibility in January
South San Francisco, 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).
South San Francisco, California, USA
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