December weather forecastRock Island, TN
December
Weather in December
December, the first month of the winter in Rock Island, is also a frosty month, with temperature in the range of an average low of 35.2°F (1.8°C) and an average high of 48.9°F (9.4°C).Temperature
A moderate decline in average high-temperatures is noted in December, moving from a refreshing 56.5°F (13.6°C) in November to a frosty 48.9°F (9.4°C). Rock Island's nights in December cool down to an average low-temperature of 35.2°F (1.8°C).Humidity
The most humid month in Rock Island, Tennessee, is December, with an average relative humidity of 81%.Rainfall
In December, the rain falls for 12.4 days. Throughout December, 2.24" (57mm) of precipitation is accumulated. In Rock Island, during the entire year, the rain falls for 177.3 days and collects up to 31.02" (788mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In Rock Island, Tennessee, during December, snow falls for 1.6 days and regularly aggregates up to 0.16" (4mm) of snow. In Rock Island, during the entire year, snow falls for 11 days and aggregates up to 1.61" (41mm) of snow.Daylight
With an average of 9h and 48min of daylight, December has the shortest days of the year in Rock Island.On the first day of the month, sunrise is at 6:34 am and sunset at 4:28 pm. On the last day of December, sunrise is at 6:52 am and sunset at 4:39 pm CST.
Sunshine
The average sunshine in December is 4.8h.UV index
January and December, with an average maximum UV index of 2, are months with the lowest UV index in Rock Island. A UV Index estimate of 2, and below, represents a minimal health hazard from exposure to the Sun's UV rays for ordinary individuals.Note: A typical high UV index of 2 in December suggests the following recommendations:
While many people can endure lengthy sun exposure, it remains imperative to safeguard babies, children, and fair-skinned individuals. Avoiding direct sunlight during midday hours helps reduce the risk from intense UV radiation. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Watch out! The Sun's UV radiation can be nearly magnified twofold due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rock Island, TN
- Average high temperature in December: 48.9°F
The warmest month (with the highest average high temperature) is July (86°F).
The month with the lowest average high temperature is January (44.2°F).
- Average low temperature in December: 35.2°F
The month with the highest average low temperature is July (65.8°F).
The coldest month (with the lowest average low temperature) is January (29.8°F).
Average pressure in December
Rock Island, TN
- Average pressure in December: 30.15"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in December
Rock Island, TN
- Average wind speed in December: 6.6mph
The windiest month (with the highest average wind speed) is February (7.4mph).
The calmest month (with the lowest average wind speed) is August (4.2mph).
Average humidity in December
Rock Island, TN
- Average humidity in December: 81%
The month with the highest relative humidity is December (81%).
The months with the lowest relative humidity are October and November (76%).
Average rainfall in December
Rock Island, TN
- Average rainfall in December: 2.24"
The wettest month (with the highest rainfall) is July (3.82").
The driest month (with the least rainfall) is November (1.65").
Average rainfall days in December
Rock Island, TN
- Average rainfall days in December: 12.4 days
The month with the highest number of rainy days is July (20.9 days).
The month with the least rainy days is November (9.3 days).
Average snowfall in December
Rock Island, TN
- Average snowfall in December: 0.16"
The month with the highest snowfall is February (0.51").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Rock Island, TN
- Average snowfall days in December: 1.6 days
The month with the highest number of snowfall days is January (3.6 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Rock Island, TN
- Average daylight in December: 9h and 48min
The month with the longest days is June (Average daylight: 14h and 30min).
The month with the shortest days is December (Average daylight: 9h and 48min).
- Average sunshine in December: 4h and 48min
The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is February (Average sunshine: 4h and 24min).
Average sunshine days in December
Rock Island, TN
- Average sunshine days in December: 16.7 days
The month with the most sunshine days is November (18.5 days).
The month with the least sunshine days is July (8.4 days).
Average UV index in December
Rock Island, TN
- 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 and December (UV index 2).
Average cloud cover in December
Rock Island, TN
- Average cloud cover in December: 52
The month with the most cloud cover is February (Cloud cover 54).
The month with the least cloud cover is June (Cloud cover 30).
Average visibility in December
Rock Island, TN
- Average visibility in December: 5mi
The months with the highest visibility are February, April, June, October and November (6mi).
The months with the lowest visibility are January, March, May, July, August, September and December (5mi).
