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
January's onset brings an average high-temperature of a still mild 58.3°F (14.6°C), showing a minute difference from December's 56.8°F (13.8°C). Throughout the January nights, Sunnyvale encounters a low-temperature of 44.6°F (7°C).Humidity
In January, the average relative humidity is 72%.Rainfall
In January, the rain falls for 6.3 days. Throughout January, 0.55" (14mm) of precipitation is accumulated. In Sunnyvale, during the entire year, the rain falls for 50 days and collects up to 3.9" (99mm) of precipitation.Daylight
In Sunnyvale, California, the average length of the day in January is 9h and 56min.On the first day of January, sunrise is at 7:22 am and sunset at 5:00 pm. On the last day of the month, sunrise is at 7:12 am and sunset at 5:30 pm PST.
Sunshine
The average sunshine in January in Sunnyvale is 6.3h.UV index
In January, the average daily maximum UV index is 4. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV rays for the ordinary person.Note: The UV index of 4 during January leads to these advisories:
Take care. Persons with lighter skin might suffer burns in less than 30 minutes. Considering the strength of solar radiation at midday, one should avoid direct Sun exposure. Counter UV radiation's ill effects with clothing designed for sun safety and UV-resistant eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in January?
What is the average humidity in January?
How many days does it rain in January?
What is the average length of the day in January?
When are sunrise and sunset in January?
How long on average sun shines in January?
What is the UV index intensity in January?
Average temperature in January
Sunnyvale, CA
- Average high temperature in January: 58.3°F
The warmest month (with the highest average high temperature) is July (79.9°F).
The month with the lowest average high temperature is December (56.8°F).
- Average low temperature in January: 44.6°F
The month with the highest average low temperature is August (56.8°F).
The coldest months (with the lowest average low temperature) are February and December (44.2°F).
Average pressure in January
Sunnyvale, 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 and September (29.92"Hg).
Average wind speed in January
Sunnyvale, CA
- Average wind speed in January: 4.9mph
The windiest month (with the highest average wind speed) is April (6.2mph).
The calmest month (with the lowest average wind speed) is September (4.6mph).
Average humidity in January
Sunnyvale, CA
- Average humidity in January: 72%
The month with the highest relative humidity is March (73%).
The months with the lowest relative humidity are September and October (63%).
Average rainfall in January
Sunnyvale, CA
- Average rainfall in January: 0.55"
The wettest months (with the highest rainfall) are February and March (0.75").
The driest month (with the least rainfall) is July (0").
Average rainfall days in January
Sunnyvale, CA
- Average rainfall days in January: 6.3 days
The month with the highest number of rainy days is March (9.6 days).
The month with the least rainy days is August (0.4 days).
Average daylight in January /
Average sunshine in January
Sunnyvale, 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 2min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 54min).
Average sunshine days in January
Sunnyvale, CA
- Average sunshine days in January: 23.8 days
The month with the most sunshine days is August (30.1 days).
The month with the least sunshine days is March (19.9 days).
Average UV index in January
Sunnyvale, CA
- Average UV index in January: 4
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are February, November and December (UV index 3).
Average cloud cover in January
Sunnyvale, 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 7).
Average visibility in January
Sunnyvale, 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).
Sunnyvale, California, USA
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