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
January
Weather in January
Temperature
The arrival of January in Santa Rosa sees an average high-temperature of a still moderate 57.2°F (14°C), hardly diverging from December's 55.6°F (13.1°C). In Santa Rosa, an average low-temperature of 43.2°F (6.2°C) is recorded during January nights.Humidity
In Santa Rosa, California, the average relative humidity in January is 75%.Rainfall
In Santa Rosa, during January, the rain falls for 10 days and regularly aggregates up to 2.01" (51mm) of precipitation. In Santa Rosa, California, during the entire year, the rain falls for 72.8 days and collects up to 12.01" (305mm) of precipitation.Daylight
The average length of the day in January in Santa Rosa is 9h and 51min.On the first day of January, sunrise is at 7:28 am and sunset at 5:00 pm. On the last day of the month, sunrise is at 7:16 am and sunset at 5:31 pm PST.
Sunshine
In January, the average sunshine is 5.8h.UV index
January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index in Santa Rosa. A UV Index value of 3 to 5 symbolizes a medium health hazard from unsafe exposure to UV radiation for the ordinary person.Note: The maximum daily UV index of 3 in January converts into the following recommendations:
Act with care - The need to guard against sun damage is communicated. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in Santa Rosa in January?
What is the average humidity in January in Santa Rosa?
How many days does it rain in January in Santa Rosa?
How many hours of daylight does Santa Rosa have in January?
When are sunrise and sunset in January in Santa Rosa?
How many hours of sunshine does Santa Rosa have in January?
When is the lowest UV index in Santa Rosa?
What is the UV index reading in January in Santa Rosa?
Average temperature in January
Santa Rosa, CA
- Average high temperature in January: 57.2°F
The warmest month (with the highest average high temperature) is August (79.7°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in January: 43.2°F
The months with the highest average low temperature are August and September (54.7°F).
The coldest month (with the lowest average low temperature) is December (41.9°F).
Average pressure in January
Santa Rosa, 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
Santa Rosa, CA
- Average wind speed in January: 5.2mph
The windiest month (with the highest average wind speed) is May (7.1mph).
The calmest month (with the lowest average wind speed) is November (4.9mph).
Average humidity in January
Santa Rosa, CA
- Average humidity in January: 75%
The month with the highest relative humidity is March (77%).
The month with the lowest relative humidity is September (63%).
Average rainfall in January
Santa Rosa, CA
- Average rainfall in January: 2.01"
The wettest month (with the highest rainfall) is February (2.64").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in January
Santa Rosa, CA
- Average rainfall days in January: 10 days
The month with the highest number of rainy days is March (12.6 days).
The month with the least rainy days is August (0.8 days).
Average daylight in January /
Average sunshine in January
Santa Rosa, CA
- Average daylight in January: 9h and 5min
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 30min).
- Average sunshine in January: 5h and 5min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in January
Santa Rosa, CA
- Average sunshine days in January: 19.9 days
The month with the most sunshine days is July (27.2 days).
The month with the least sunshine days is March (17.1 days).
Average UV index in January
Santa Rosa, CA
- Average UV index in January: 3
The month with the highest UV index is June (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in January
Santa Rosa, 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 July (Cloud cover 9).
Average visibility in January
Santa Rosa, 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).