December weather forecastFlat Rock, ID
December
Weather in December
The first month of the winter, December, is also a subzero cold month in Flat Rock, Idaho, with an average temperature varying between 6.8°F (-14°C) and 22.3°F (-5.4°C).Temperature
With average high temperatures of 22.3°F (-5.4°C) and lows of 6.8°F (-14°C), December is the coldest month.Humidity
In December, the average relative humidity is 92%.Rainfall
In Flat Rock, during December, the rain falls for 5.4 days and regularly aggregates up to 1.97" (50mm) of precipitation. Throughout the year, there are 106.1 rainfall days, and 20.83" (529mm) of precipitation is accumulated.Snowfall
Months with snowfall are January through July, September through December. In Flat Rock, in December, snow falls for 23 days, with typically accumulated 16.5" (419mm) of snow. In Flat Rock, during the entire year, snow falls for 138.1 days and aggregates up to 107.64" (2734mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 54min of daylight.On the first day of December, sunrise is at 7:42 am and sunset at 4:46 pm. On the last day of the month, sunrise is at 8:01 am and sunset at 4:55 pm MST.
Sunshine
In December, the average sunshine is 4.2h.UV index
January, February, November and December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a low threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.Note: The maximum daily UV index of 1 during December translates into the following directions:
While most people can stay under the sun for an hour without burning, children must always be guarded against sun exposure. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage. Take to heart! Snow reflection can almost magnify the Sun's UV radiation twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Flat Rock, ID
- Average high temperature in December: 22.3°F
The warmest month (with the highest average high temperature) is July (77.4°F).
The month with the lowest average high temperature is December (22.3°F).
- Average low temperature in December: 6.8°F
The month with the highest average low temperature is August (46.6°F).
The coldest months (with the lowest average low temperature) are January and December (6.8°F).
Average pressure in December
Flat Rock, ID
- Average pressure in December: 30.24"Hg
The month with the highest atmospheric pressure is January (30.26"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Flat Rock, ID
- Average wind speed in December: 4.5mph
The windiest month (with the highest average wind speed) is June (6.3mph).
The calmest month (with the lowest average wind speed) is January (4.4mph).
Average humidity in December
Flat Rock, ID
- Average humidity in December: 92%
The months with the highest relative humidity are January and February (94%).
The month with the lowest relative humidity is August (47%).
Average rainfall in December
Flat Rock, ID
- Average rainfall in December: 1.97"
The wettest month (with the highest rainfall) is February (2.64").
The driest month (with the least rainfall) is July (0.47").
Average rainfall days in December
Flat Rock, ID
- Average rainfall days in December: 5.4 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is January (3.8 days).
Average snowfall in December
Flat Rock, ID
- Average snowfall in December: 16.5"
The month with the highest snowfall is January (19.84").
The month with the least snowfall is August (0").
Average snowfall days in December
Flat Rock, ID
- Average snowfall days in December: 23 days
The month with the highest number of snowfall days is December (23 days).
The month with the least snowfall days is August (0 days).
Average daylight in December /
Average sunshine in December
Flat Rock, ID
- Average daylight in December: 8h and 54min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in December: 4h and 12min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 48min).
Average sunshine days in December
Flat Rock, ID
- Average sunshine days in December: 7.7 days
The month with the most sunshine days is July (21.2 days).
The month with the least sunshine days is February (5.9 days).
Average UV index in December
Flat Rock, ID
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in December
Flat Rock, ID
- Average cloud cover in December: 61
The month with the most cloud cover is February (Cloud cover 67).
The month with the least cloud cover is July (Cloud cover 13).
Average visibility in December
Flat Rock, ID
- Average visibility in December: 3mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The months with the lowest visibility are January, February and December (3mi).





