December weather forecastGreenfield, CA
December
Weather in December
The first month of the winter, December, is also a moderate month in Greenfield, California, with an average temperature varying between 40.8°F (4.9°C) and 56.8°F (13.8°C).Temperature
With average high and low temperatures of 56.8°F (13.8°C) and 40.8°F (4.9°C) respectively, December is Greenfield's coldest month.Humidity
The average relative humidity in December is 68%.Rainfall
The month with the most rainfall is December, when the rain falls for 9.2 days and typically aggregates up to 1.89" (48mm) of precipitation.Daylight
December has the shortest days of the year in Greenfield, with an average of 9h and 42min of daylight.On the first day of the month, sunrise is at 6:58 am and sunset at 4:50 pm. On the last day of December, sunrise is at 7:16 am and sunset at 5:00 pm PST.
Sunshine
The month with the least sunshine is December, with an average of 6.1h of sunshine.UV index
February, November and December, with an average maximum UV index of 3, are months with the lowest UV index. A UV Index of 3 to 5 symbolizes a moderate health risk from unprotected exposure to Sun's UV rays for average individuals.Note: In December, the maximum UV index of 3 translates into these guidelines:
Put precautions into practice - Protective measures against sun-induced damage are advised. UV radiation from the Sun is most dangerous during midday; take precautions and seek shade. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Greenfield, CA
- Average high temperature in December: 56.8°F
The warmest month (with the highest average high temperature) is July (89.1°F).
The month with the lowest average high temperature is December (56.8°F).
- Average low temperature in December: 40.8°F
The month with the highest average low temperature is August (58.6°F).
The coldest month (with the lowest average low temperature) is December (40.8°F).
Average pressure in December
Greenfield, CA
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in December
Greenfield, CA
- Average wind speed in December: 4.7mph
The windiest month (with the highest average wind speed) is May (6.3mph).
The calmest month (with the lowest average wind speed) is November (4.5mph).
Average humidity in December
Greenfield, CA
- Average humidity in December: 68%
The month with the highest relative humidity is February (70%).
The month with the lowest relative humidity is July (46%).
Average rainfall in December
Greenfield, CA
- Average rainfall in December: 1.89"
The wettest month (with the highest rainfall) is December (1.89").
The driest month (with the least rainfall) is August (0.04").
Average rainfall days in December
Greenfield, CA
- Average rainfall days in December: 9.2 days
The month with the highest number of rainy days is March (11.8 days).
The month with the least rainy days is August (0.4 days).
Average daylight in December /
Average sunshine in December
Greenfield, CA
- Average daylight in December: 9h and 42min
The month with the longest days is June (Average daylight: 14h and 36min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in December: 6h and 6min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 6min).
Average sunshine days in December
Greenfield, CA
- Average sunshine days in December: 20.6 days
The month with the most sunshine days is August (30.1 days).
The month with the least sunshine days is March (18.3 days).
Average UV index in December
Greenfield, 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 February, November and December (UV index 3).
Average cloud cover in December
Greenfield, CA
- Average cloud cover in December: 32
The months with the most cloud cover are March and December (Cloud cover 32).
The months with the least cloud cover are July and August (Cloud cover 4).
Average visibility in December
Greenfield, 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).
