December weather forecastRackerby, CA
December
Weather in December
The first month of the winter, December, is still a cool month in Rackerby, California, with an average temperature varying between 53.6°F (12°C) and 39.7°F (4.3°C).Temperature
Rackerby witnesses the coldest weather in December, with temperatures averaging a high of 53.6°F (12°C) and a low of 39.7°F (4.3°C).Humidity
The average relative humidity in December in Rackerby is 68%.Rainfall
In December, the rain falls for 9.8 days. Throughout December, 2.72" (69mm) of precipitation is accumulated. In Rackerby, during the entire year, the rain falls for 71.4 days and collects up to 15.31" (389mm) of precipitation.Snowfall
In Rackerby, snow does not fall in January, March through December.Daylight
The month with the shortest days is December, with an average of 9h and 24min of daylight.On the first day of the month, sunrise is at 7:07 am and sunset at 4:42 pm. On the last day of December, sunrise is at 7:25 am and sunset at 4:52 pm PST.
Sunshine
December has the least sunshine of the year in Rackerby, with an average of 5.8h of sunshine.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 medium health hazard from exposure to the Sun's UV rays for average individuals.Note: The UV index of 3 during December leads to these advisories:
Make use of precautions - It is urged to ward off sun damage. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Enhance your sun protection with tightly woven, yet airy clothing. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rackerby, CA
- Average high temperature in December: 53.6°F
The warmest month (with the highest average high temperature) is July (93.9°F).
The month with the lowest average high temperature is December (53.6°F).
- Average low temperature in December: 39.7°F
The month with the highest average low temperature is July (62.1°F).
The coldest month (with the lowest average low temperature) is December (39.7°F).
Average pressure in December
Rackerby, CA
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in December
Rackerby, CA
- Average wind speed in December: 5.2mph
The windiest month (with the highest average wind speed) is March (6mph).
The calmest months (with the lowest average wind speed) are August and November (5mph).
Average humidity in December
Rackerby, CA
- Average humidity in December: 68%
The month with the highest relative humidity is March (74%).
The month with the lowest relative humidity is July (35%).
Average rainfall in December
Rackerby, CA
- Average rainfall in December: 2.72"
The wettest month (with the highest rainfall) is March (2.87").
The driest month (with the least rainfall) is July (0.04").
Average rainfall days in December
Rackerby, CA
- Average rainfall days in December: 9.8 days
The month with the highest number of rainy days is March (12.8 days).
The month with the least rainy days is July (1.6 days).
Average snowfall in December
Rackerby, CA
- Average snowfall in December: 0"
The month with the highest snowfall is February (0.04").
The months with the least snowfall are January, March, April, May, June, July, August, September, October, November and December (0").
Average snowfall days in December
Rackerby, CA
- Average snowfall days in December: 0.1 days
The month with the highest number of snowfall days is February (0.2 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October and November (0 days).
Average daylight in December /
Average sunshine in December
Rackerby, CA
- Average daylight in December: 9h and 24min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in December: 5h and 48min
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 48min).
Average sunshine days in December
Rackerby, CA
- Average sunshine days in December: 20.7 days
The month with the most sunshine days is July (29.1 days).
The month with the least sunshine days is March (17.4 days).
Average UV index in December
Rackerby, CA
- Average UV index in December: 3
The months with the highest UV index are June and July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in December
Rackerby, CA
- Average cloud cover in December: 35
The month with the most cloud cover is March (Cloud cover 39).
The month with the least cloud cover is July (Cloud cover 4).
Average visibility in December
Rackerby, 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).





