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
Fullerton's average high-temperature in January is a still enjoyable 66.2°F (19°C), marking an insignificant difference from the 64°F (17.8°C) of December. Fullerton's temperature tends to fall to an average low of 51.4°F (10.8°C) during the nights of January.Humidity
The average relative humidity in January is 54%.Rainfall
In Fullerton, during January, the rain falls for 4.8 days and regularly aggregates up to 1.14" (29mm) of precipitation. In Fullerton, during the entire year, the rain falls for 52.5 days and collects up to 7.09" (180mm) of precipitation.Daylight
In January, the average length of the day is 10h and 12min.On the first day of January, sunrise is at 6:56 am and sunset at 4:53 pm. On the last day of the month, sunrise is at 6:49 am and sunset at 5:21 pm PST.
Sunshine
The average sunshine in January is 6.9h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 4. A UV Index estimate of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for the ordinary person.Note: A daily maximum UV index of 4 in January translates into the following instructions:
Make use of precautions - Suggestions to resist sunburn are communicated. It's crucial to reduce time in the direct Sun around mid-day due to the intense solar radiation. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the temperature in January?
What is the average humidity in January?
How much does it rain in January?
What is the average length of the day in January?
What time are sunrise and sunset in January?
How many hours of sunshine does Fullerton have in January?
What is the month with the lowest UV index?
What is the UV index intensity in January?
Average temperature in January
Fullerton, CA
- Average high temperature in January: 66.2°F
The warmest month (with the highest average high temperature) is August (83.5°F).
The month with the lowest average high temperature is December (64°F).
- Average low temperature in January: 51.4°F
The month with the highest average low temperature is August (65.5°F).
The coldest month (with the lowest average low temperature) is February (50.2°F).
Average pressure in January
Fullerton, CA
- Average pressure in January: 30.1"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.88"Hg).
Average wind speed in January
Fullerton, CA
- Average wind speed in January: 5.2mph
The windiest month (with the highest average wind speed) is April (6mph).
The calmest months (with the lowest average wind speed) are September and October (4.7mph).
Average humidity in January
Fullerton, CA
- Average humidity in January: 54%
The month with the highest relative humidity is June (65%).
The month with the lowest relative humidity is November (51%).
Average rainfall in January
Fullerton, CA
- Average rainfall in January: 1.14"
The wettest month (with the highest rainfall) is December (1.54").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in January
Fullerton, CA
- Average rainfall days in January: 4.8 days
The month with the highest number of rainy days is March (7.3 days).
The month with the least rainy days is June (1.5 days).
Average daylight in January /
Average sunshine in January
Fullerton, CA
- Average daylight in January: 10h and 1min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in January: 6h and 5min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days in January
Fullerton, CA
- Average sunshine days in January: 25.2 days
The month with the most sunshine days is August (25.8 days).
The month with the least sunshine days is February (20.6 days).
Average UV index in January
Fullerton, CA
- Average UV index in January: 4
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 4).
Average cloud cover in January
Fullerton, CA
- Average cloud cover in January: 20
The months with the most cloud cover are March and December (Cloud cover 22).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in January
Fullerton, 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).
Fullerton, California, USA
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