Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December, noted for its average high-temperature of 54.7°F (12.6°C) and an average low-temperature of 41.4°F (5.2°C), is considered the coldest month.Humidity
In December, the average relative humidity is 71%.Rainfall
In Vacaville, during December, the rain falls for 6.6 days and regularly aggregates up to 0.63" (16mm) of precipitation. Throughout the year, there are 47.1 rainfall days, and 4.17" (106mm) of precipitation is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 30min of daylight.On the first day of the month, sunrise is at 7:06 am and sunset at 4:47 pm. On the last day of December, in Vacaville, sunrise is at 7:24 am and sunset at 4:57 pm PST.
Sunshine
The month with the least sunshine is December, with an average of 5.7h of sunshine.UV index
The months with the lowest UV index in Vacaville, California, are January, February, November and December, with an average maximum UV index of 3. A UV Index reading of 3 to 5 represents a medium vulnerability from unsafe exposure to UV radiation for average individuals.Note: In December, a daily maximum UV index of 3 leads to the following instructions:
Heed the precautions - It is counselled to guard against solar damage. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the coldest months in Vacaville?
What is the temperature in December in Vacaville?
What is the average humidity in December in Vacaville?
How much does it rain in Vacaville in December?
What is the month with the shortest days in Vacaville?
How many hours of daylight does Vacaville have in December?
When is the sunrise / sunset in December in Vacaville?
What is the month with the least sunshine in Vacaville?
How long on average sun shines in December in Vacaville?
What is the month with the lowest UV index in Vacaville?
What is the UV index intensity in December in Vacaville?
Average temperature in December
Vacaville, CA
- Average high temperature in December: 54.7°F
The warmest month (with the highest average high temperature) is July (91°F).
The month with the lowest average high temperature is December (54.7°F).
- Average low temperature in December: 41.4°F
The month with the highest average low temperature is September (58.1°F).
The coldest months (with the lowest average low temperature) are January and December (41.4°F).
Average pressure in December
Vacaville, CA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June and August (29.91"Hg).
Average wind speed in December
Vacaville, CA
- Average wind speed in December: 5.2mph
The windiest months (with the highest average wind speed) are May and June (6.8mph).
The calmest months (with the lowest average wind speed) are January and November (4.7mph).
Average humidity in December
Vacaville, CA
- Average humidity in December: 71%
The month with the highest relative humidity is March (75%).
The month with the lowest relative humidity is September (48%).
Average rainfall in December
Vacaville, CA
- Average rainfall in December: 0.63"
The wettest month (with the highest rainfall) is February (0.87").
The driest months (with the least rainfall) are July, August and September (0.04").
Average rainfall days in December
Vacaville, CA
- Average rainfall days in December: 6.6 days
The month with the highest number of rainy days is March (7.2 days).
The month with the least rainy days is August (1 days).
Average daylight in December /
Average sunshine in December
Vacaville, CA
- Average daylight in December: 9h and 3min
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 December: 5h and 4min
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 42min).
Average sunshine days in December
Vacaville, CA
- Average sunshine days in December: 23.5 days
The month with the most sunshine days is July (29.8 days).
The month with the least sunshine days is February (21.5 days).
Average UV index in December
Vacaville, CA
- Average UV index in December: 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 December
Vacaville, CA
- Average cloud cover in December: 37
The months with the most cloud cover are March and December (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 5).
Average visibility in December
Vacaville, CA
- Average visibility in December: 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).
Vacaville, California, USA
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