Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
The arrival of December brings a significant change in Rockville's weather, with average high-temperatures dropping from November's cold 38.7°F (3.7°C) to a subzero cold 23.9°F (-4.5°C). Throughout the month of December, Rockville sees a steady low-temperature average of 13.5°F (-10.3°C).Humidity
In Rockville, the average relative humidity in December is 87%.Rainfall
In December, the rain falls for 3.4 days. Throughout December, 0.91" (23mm) of precipitation is accumulated. In Rockville, during the entire year, the rain falls for 109.6 days and collects up to 17.52" (445mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. The month with the most snowfall is December, when snow falls for 12.6 days and typically aggregates up to 4.13" (105mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 48min of daylight.On the first day of the month, sunrise is at 7:37 am and sunset at 4:35 pm. On the last day of December, sunrise is at 7:57 am and sunset at 4:44 pm CST.
Sunshine
The average sunshine in December is 3.4h.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 estimate of 2, and below, represents a minimal health vulnerability from unprotected exposure to Sun's UV rays for ordinary individuals.Note: A maximum high UV index of 1 in December translates into the following recommendations:
Many can withstand an hour in the sun without burning, yet children must always have protection against sunlight. The Sun is most powerful around mid-day, so it's a good practice to reduce direct exposure. A wide-brim hat offers excellent sun protection for the eyes, ears, face, and neck. Sunglasses with UVA and UVB protection significantly reduce eye damage from sun exposure. Remember this! The UV radiation of the Sun can be nearly doubled by the reflective properties of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December in Rockville?
What is the average humidity in December?
How much does it rain in December?
When does it snow the most?
How much does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
When are sunrise and sunset in December?
How many hours of sunshine does Rockville have in December?
When is the lowest UV index?
How high is the UV index in December?
Average temperature in December
Rockville, MN
- Average high temperature in December: 23.9°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (18.7°F).
- Average low temperature in December: 13.5°F
The month with the highest average low temperature is July (61.2°F).
The coldest month (with the lowest average low temperature) is January (5.4°F).
Average pressure in December
Rockville, MN
- Average pressure in December: 30.11"Hg
The months with the highest atmospheric pressure are January and February (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in December
Rockville, MN
- Average wind speed in December: 8.7mph
The windiest month (with the highest average wind speed) is April (9.3mph).
The calmest months (with the lowest average wind speed) are July and August (7.1mph).
Average humidity in December
Rockville, MN
- Average humidity in December: 87%
The month with the highest relative humidity is January (91%).
The months with the lowest relative humidity are April and May (70%).
Average rainfall in December
Rockville, MN
- Average rainfall in December: 0.91"
The wettest month (with the highest rainfall) is June (3.03").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days in December
Rockville, MN
- Average rainfall days in December: 3.4 days
The month with the highest number of rainy days is June (15.3 days).
The month with the least rainy days is January (2.2 days).
Average snowfall in December
Rockville, MN
- Average snowfall in December: 4.13"
The month with the highest snowfall is December (4.13").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Rockville, MN
- Average snowfall days in December: 12.6 days
The month with the highest number of snowfall days is January (14.4 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Rockville, MN
- Average daylight in December: 8h and 5min
The month with the longest days is June (Average daylight: 15h and 36min).
The month with the shortest days is December (Average daylight: 8h and 48min).
- Average sunshine in December: 3h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 18min).
Average sunshine days in December
Rockville, MN
- Average sunshine days in December: 17.4 days
The month with the most sunshine days is September (19.2 days).
The month with the least sunshine days is June (12.4 days).
Average UV index in December
Rockville, MN
- Average UV index in December: 1
The month with the highest UV index is July (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 1).
Average cloud cover in December
Rockville, MN
- Average cloud cover in December: 64
The month with the most cloud cover is January (Cloud cover 67).
The months with the least cloud cover are July and August (Cloud cover 32).
Average visibility in December
Rockville, MN
- Average visibility in December: 5mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).
Rockville, Minnesota, USA
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