December weather forecastAtwater, CA
December
Weather in December
The first month of the winter, December, is also a moderate month in Atwater, California, with an average temperature varying between 41.9°F (5.5°C) and 56.1°F (13.4°C).Temperature
December brings the lowest temperatures, with an average high of 56.1°F (13.4°C) and an average low of 41.9°F (5.5°C).Humidity
In Atwater, the average relative humidity in December is 69%.Rainfall
The wettest months are March and December, with an average 0.55" (14mm) of rainfall.Daylight
With an average of 9h and 36min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 6:58 am and sunset at 4:44 pm. On the last day of December, sunrise is at 7:16 am and sunset at 4:55 pm PST.
Sunshine
With an average of 6.2h 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 rays for average individuals.Note: In December, the maximum UV index of 3 suggests these recommendations:
Put precautions into practice - Guidance to elude sunburn is provided. Sun exposure should be minimized, especially during midday, to avoid harmful UV radiation. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Atwater, CA
- Average high temperature in December: 56.1°F
The warmest month (with the highest average high temperature) is July (98.6°F).
The month with the lowest average high temperature is December (56.1°F).
- Average low temperature in December: 41.9°F
The month with the highest average low temperature is July (63.9°F).
The coldest month (with the lowest average low temperature) is December (41.9°F).
Average pressure in December
Atwater, CA
- Average pressure in December: 30.12"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in December
Atwater, CA
- Average wind speed in December: 5.3mph
The windiest month (with the highest average wind speed) is June (7.6mph).
The calmest month (with the lowest average wind speed) is November (4.9mph).
Average humidity in December
Atwater, CA
- Average humidity in December: 69%
The month with the highest relative humidity is January (71%).
The month with the lowest relative humidity is July (34%).
Average rainfall in December
Atwater, CA
- Average rainfall in December: 0.55"
The wettest months (with the highest rainfall) are March and December (0.55").
The driest months (with the least rainfall) are June, July, August and September (0.04").
Average rainfall days in December
Atwater, CA
- Average rainfall days in December: 5.1 days
The month with the highest number of rainy days is March (6.8 days).
The month with the least rainy days is June (0.5 days).
Average daylight in December /
Average sunshine in December
Atwater, CA
- Average daylight in December: 9h and 36min
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 December: 6h and 12min
The month with the most sunshine is July (Average sunshine: 12h and 12min).
The month with the least sunshine is December (Average sunshine: 6h and 12min).
Average sunshine days in December
Atwater, CA
- Average sunshine days in December: 24.9 days
The month with the most sunshine days is August (28.9 days).
The month with the least sunshine days is February (23 days).
Average UV index in December
Atwater, CA
- Average UV index in December: 3
The months with the highest UV index are June, July and August (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in December
Atwater, CA
- Average cloud cover in December: 31
The month with the most cloud cover is December (Cloud cover 31).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in December
Atwater, 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).
