December weather forecastRock Hill, SC
December
Weather in December
December in Rock Hill traditionally introduces the beginning of winter weather conditions. The daylight hours are at their shortest, staying around 9.8 hours, and the abundance of sunshine tapers off to a yearly low of 5.3 hours. The city registers its highest precipitation, averaging 3.46" (88mm) of rain, aligning with the onset of the winter rainy season. An interesting element introduced by December weather in Rock Hill is snowfall, after a lack of it since the past April, December sees an average of 0.87" (22mm) of snow. This month, presenting colder climatic conditions, defines the ending note of the year in Rock Hill with a blend of cold rain and bits of snow.Temperature
The advent of December brings a subtle shift in temperature, with the average high moving from a refreshing 59.9°F (15.5°C) in November to a cool 53.1°F (11.7°C). In December, the nighttime temperature in Rock Hill, South Carolina, lowers to an average of 39°F (3.9°C).Humidity
With an average relative humidity of 75%, December is the most humid month in Rock Hill.Rainfall
The month with the most rainfall in Rock Hill is December, when the rain falls for 11.6 days and typically aggregates up to 3.46" (88mm) of precipitation.Snowfall
Months with snowfall in Rock Hill are January through March and December. December is the first month it typically snows. Throughout December, in the average 0.5 snowfall days, it receives 0.87" (22mm) of snow. Throughout the year, in Rock Hill, there are 3.9 snowfall days, and 3.66" (93mm) of snow is accumulated.Daylight
December has the shortest days of the year in Rock Hill, with an average of 9h and 54min of daylight.On the first day of December in Rock Hill, sunrise is at 7:14 am and sunset at 5:12 pm. On the last day of the month, sunrise is at 7:31 am and sunset at 5:23 pm EST.
Sunshine
The month with the least sunshine in Rock Hill, South Carolina, is December, with an average of 5.3h of sunshine.UV index
January and December, with an average maximum UV index of 2, are months with the lowest UV index in Rock Hill. A UV Index value of 2, and less, symbolizes a low health risk from exposure to the Sun's UV rays for ordinary individuals.Note: An average UV index of 2 in December transforms into this advice:
Most individuals can handle sun exposure for up to an hour without burning, but children must always be shielded from sun exposure. The Sun's radiation is especially intense around midday; try to stay in shade during this period. Sunglasses that guard against UVA and UVB rays are pivotal in minimizing sun-induced ocular damage. Be aware! The intensity of the Sun's UV radiation can be amplified nearly twice due to snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Rock Hill, SC
- Average high temperature in December: 53.1°F
The warmest month (with the highest average high temperature) is July (91.2°F).
The month with the lowest average high temperature is January (49.6°F).
- Average low temperature in December: 39°F
The month with the highest average low temperature is July (70.7°F).
The coldest month (with the lowest average low temperature) is January (34.2°F).
Average pressure in December
Rock Hill, SC
- Average pressure in December: 30.14"Hg
The month with the highest atmospheric pressure is November (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in December
Rock Hill, SC
- Average wind speed in December: 6.6mph
The windiest month (with the highest average wind speed) is April (7.7mph).
The calmest month (with the lowest average wind speed) is August (4.7mph).
Average humidity in December
Rock Hill, SC
- Average humidity in December: 75%
The month with the highest relative humidity is December (75%).
The month with the lowest relative humidity is July (69%).
Average rainfall in December
Rock Hill, SC
- Average rainfall in December: 3.46"
The wettest month (with the highest rainfall) is December (3.46").
The driest month (with the least rainfall) is September (1.97").
Average rainfall days in December
Rock Hill, SC
- Average rainfall days in December: 11.6 days
The month with the highest number of rainy days is July (18.1 days).
The month with the least rainy days is November (9.6 days).
Average snowfall in December
Rock Hill, SC
- Average snowfall in December: 0.87"
The month with the highest snowfall is February (1.34").
The months with the least snowfall are April, May, June, July, August, September, October and November (0").
Average snowfall days in December
Rock Hill, SC
- Average snowfall days in December: 0.5 days
The month with the highest number of snowfall days is February (1.7 days).
The months with the least snowfall days are April, May, June, July, August, September, October and November (0 days).
Average daylight in December /
Average sunshine in December
Rock Hill, SC
- Average daylight in December: 9h and 54min
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 54min).
- Average sunshine in December: 5h and 18min
The month with the most sunshine is July (Average sunshine: 10h and 42min).
The month with the least sunshine is December (Average sunshine: 5h and 18min).
Average sunshine days in December
Rock Hill, SC
- Average sunshine days in December: 17.5 days
The month with the most sunshine days is October (20.3 days).
The month with the least sunshine days is July (10.8 days).
Average UV index in December
Rock Hill, SC
- Average UV index in December: 2
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in December
Rock Hill, SC
- Average cloud cover in December: 43
The month with the most cloud cover is February (Cloud cover 44).
The month with the least cloud cover is June (Cloud cover 30).
Average visibility in December
Rock Hill, SC
- 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).
