December weather forecastPacheco, CA
December
Weather in December
December, the first month of the winter in Pacheco, is still a refreshing month, with an average temperature varying between 55.6°F (13.1°C) and 42.4°F (5.8°C).Temperature
Temperature readings reach their annual highs in December, averaging 55.6°F (13.1°C) and a minimum average of 42.4°F (5.8°C).Humidity
The average relative humidity in December is 70%.Rainfall
In Pacheco, in December, it is raining for 7.5 days, with typically 0.59" (15mm) of accumulated precipitation. Throughout the year, there are 49.3 rainfall days, and 3.82" (97mm) of precipitation is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 36min of daylight.On the first day of the month, sunrise is at 7:06 am and sunset at 4:49 pm. On the last day of December, sunrise is at 7:24 am and sunset at 4:59 pm PST.
Sunshine
With an average of 5.7h of sunshine, December has the least sunshine of the year.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 3. A UV Index estimate of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: In December, the maximum UV index of 3 transforms into these recommendations:
Be careful. Light complexion individuals might get burns in fewer than 30 minutes. Solar radiation peaks around mid-day, so it's wise to limit exposure to the Sun at this time. Employ a hat with a wide brim for robust protection, cutting UV exposure by half.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Pacheco, CA
- Average high temperature in December: 55.6°F
The warmest month (with the highest average high temperature) is July (83.7°F).
The month with the lowest average high temperature is December (55.6°F).
- Average low temperature in December: 42.4°F
The month with the highest average low temperature is September (57.4°F).
The coldest month (with the lowest average low temperature) is January (42.3°F).
Average pressure in December
Pacheco, CA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Pacheco, CA
- Average wind speed in December: 5mph
The windiest month (with the highest average wind speed) is May (7.6mph).
The calmest month (with the lowest average wind speed) is November (4.5mph).
Average humidity in December
Pacheco, CA
- Average humidity in December: 70%
The months with the highest relative humidity are January and March (73%).
The month with the lowest relative humidity is September (56%).
Average rainfall in December
Pacheco, CA
- Average rainfall in December: 0.59"
The wettest month (with the highest rainfall) is February (0.87").
The driest months (with the least rainfall) are June, July, August and September (0.04").
Average rainfall days in December
Pacheco, CA
- Average rainfall days in December: 7.5 days
The month with the highest number of rainy days is March (9.8 days).
The month with the least rainy days is August (0.5 days).
Average daylight in December /
Average sunshine in December
Pacheco, CA
- Average daylight in December: 9h and 36min
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 36min).
- Average sunshine in December: 5h and 42min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).
Average sunshine days in December
Pacheco, CA
- Average sunshine days in December: 22.2 days
The month with the most sunshine days is July (29.5 days).
The month with the least sunshine days is March (20 days).
Average UV index in December
Pacheco, CA
- Average UV index in December: 3
The months with the highest UV index are June 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
Pacheco, CA
- Average cloud cover in December: 36
The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 8).
Average visibility in December
Pacheco, 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).





