December weather forecastCedar Grove Knolls, MD
December
Weather in December
December, the first month of the winter in Cedar Grove Knolls, is still a chilly month, with an average temperature fluctuating between 31.1°F (-0.5°C) and 43.5°F (6.4°C).Temperature
December reveals a small adjustment in temperature, transitioning from an average high of a fresh 52.3°F (11.3°C) in November to a frosty 43.5°F (6.4°C). An average temperature of 31.1°F (-0.5°C) is recorded during the nights in December.Humidity
In Cedar Grove Knolls, Maryland, the average relative humidity in December is 78%.Rainfall
In Cedar Grove Knolls, Maryland, in December, it is raining for 10.4 days, with typically 2.24" (57mm) of accumulated precipitation. In Cedar Grove Knolls, during the entire year, the rain falls for 158.7 days and collects up to 30.91" (785mm) of precipitation.Snowfall
Months with snowfall are January through May, October through December. In December, in Cedar Grove Knolls, it is snowing for 3.5 days. Throughout December, 2.01" (51mm) of snow is accumulated. Throughout the year, there are 21.3 snowfall days, and 13.31" (338mm) of snow is accumulated.Daylight
The month with the shortest days is December, with an average of 9h and 30min of daylight.On the first day of the month, sunrise is at 7:10 am and sunset at 4:46 pm. On the last day of December, in Cedar Grove Knolls, sunrise is at 7:28 am and sunset at 4:56 pm EST.
Sunshine
In December, the average sunshine is 5.1h.UV index
The months with the lowest UV index in Cedar Grove Knolls are January, February, November and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low threat to health from exposure to the Sun's UV rays for the average person.Note: The maximum daily UV index of 2 in December converts into the following recommendations:
Extended sun exposure is not an issue for the majority. Children, infants, and fair-skinned individuals always need to be protected. Minimize direct exposure to the Sun during midday when its radiation is at its peak. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Observe! Snow reflection can nearly intensify the Sun's UV radiation twofold.
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Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Cedar Grove Knolls, MD
- Average high temperature in December: 43.5°F
The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37.8°F).
- Average low temperature in December: 31.1°F
The month with the highest average low temperature is July (66.6°F).
The coldest month (with the lowest average low temperature) is January (24.8°F).
Average pressure in December
Cedar Grove Knolls, MD
- Average pressure in December: 30.11"Hg
The month with the highest atmospheric pressure is November (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).
Average wind speed in December
Cedar Grove Knolls, MD
- Average wind speed in December: 7.3mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is August (4.8mph).
Average humidity in December
Cedar Grove Knolls, MD
- Average humidity in December: 78%
The months with the highest relative humidity are May and October (79%).
The months with the lowest relative humidity are April and July (74%).
Average rainfall in December
Cedar Grove Knolls, MD
- Average rainfall in December: 2.24"
The wettest month (with the highest rainfall) is August (3.82").
The driest month (with the least rainfall) is January (1.93").
Average rainfall days in December
Cedar Grove Knolls, MD
- Average rainfall days in December: 10.4 days
The month with the highest number of rainy days is May (17.7 days).
The month with the least rainy days is January (8.3 days).
Average snowfall in December
Cedar Grove Knolls, MD
- Average snowfall in December: 2.01"
The month with the highest snowfall is March (4.09").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Cedar Grove Knolls, MD
- Average snowfall days in December: 3.5 days
The month with the highest number of snowfall days is January (6.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Cedar Grove Knolls, MD
- Average daylight in December: 9h and 30min
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 30min).
- Average sunshine in December: 5h and 6min
The month with the most sunshine is July (Average sunshine: 10h and 48min).
The month with the least sunshine is February (Average sunshine: 4h and 54min).
Average sunshine days in December
Cedar Grove Knolls, MD
- Average sunshine days in December: 17.6 days
The month with the most sunshine days is November (19.3 days).
The month with the least sunshine days is May (10.8 days).
Average UV index in December
Cedar Grove Knolls, MD
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in December
Cedar Grove Knolls, MD
- Average cloud cover in December: 45
The month with the most cloud cover is March (Cloud cover 47).
The month with the least cloud cover is July (Cloud cover 30).
Average visibility in December
Cedar Grove Knolls, MD
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is May (5mi).
