Wrapping up the year,
December reincorporates the coldest temperatures similar to those of
January, with a high of 46°F (7.8°C). Paired with substantial rainfall and shorter daylight hours, a noticeable winter chill dominates the park. The UV index also hits its low, presenting minimal sun exposure. Despite these cold conditions, the serene winter landscape offers a distinctive charm. As the year concludes, the weather fosters a calm, pristine beauty typical of winter's embrace.
Temperature
The commencement of December in
Mammoth Cave National Park involves a temperature shift, with the average high-temperature dropping from a moderate 57.2°F (14°C) in
November to a frosty 46.4°F (8°C). The temperature dips to an average of 28.4°F (-2°C) during December nights.
Rainfall
In Mammoth Cave National Park, in December, during 12 rainfall days, 4.72" (120mm) of precipitation is typically accumulated. Throughout the year, there are 126 rainfall days, and 50.63" (1286mm) of precipitation is accumulated.
Daylight
With an average of 9h and 42min of daylight, December has the shortest days of the year.
On the first day of the month, sunrise is at 6:40 am and sunset at 4:27 pm. On the last day of December, sunrise is at 6:58 am and sunset at 4:37 pm CST.
Sunshine
January and December, with an average of 4h of sunshine, are months with the least sunshine.
UV index
The months with the lowest UV index in Mammoth Cave National Park are January and December, with an average maximum UV index of 2. A UV Index of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV rays for average individuals.
Note: An average UV index of 2 in December transforms into this advice:
Extended sunlight exposure does not pose significant problems for most people, except for children, infants, and people with fair skin who always need shielding. Being in direct Sun during midday can be harmful due to intense solar radiation; take precautions. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.