December weather forecastJoppa, IL

December

Weather in December

The first month of the winter, December, is still a chilly month in Joppa, Illinois, with an average temperature varying between 33.3°F (0.7°C) and 45.5°F (7.5°C).

Temperature

The onset of December entails a temperature shift, as the average high-temperature decreases from a fresh 54.9°F (12.7°C) in November to a chilly 45.5°F (7.5°C). In December, the recorded average low-temperature is a cold 33.3°F (0.7°C).

Humidity

In December, the average relative humidity is 78%.

Rainfall

In Joppa, in December, it is raining for 11.5 days, with typically 3.03" (77mm) of accumulated precipitation. Throughout the year, there are 160.7 rainfall days, and 36.73" (933mm) of precipitation is accumulated.

Snowfall

January through April, November and December are months with snowfall. In Joppa, Illinois, in December, during 2 snowfall days, 0.47" (12mm) of snow is typically accumulated. Throughout the year, there are 12.9 snowfall days, and 4.33" (110mm) of snow is accumulated.

Daylight

The month with the shortest days is December, with an average of 9h and 42min of daylight.
On the first day of December, sunrise is at 6:51 am and sunset at 4:38 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 4:48 pm CST.

Sunshine

In December, the average sunshine is 4.9h.

UV index

The months with the lowest UV index are January, February and December, with an average maximum UV index of 2. A UV Index estimate of 2, and below, represents a low health risk from exposure to the Sun's UV radiation for the ordinary person.
Note: A maximum daily UV index of 2 during December morphs into the following directions:
Most people can stay in the Sun for up to 1 hour without burning, apart from children that always must be protected from sun exposure. To avoid the Sun's strongest rays, limit exposure around the mid-day period. Select sunglasses that boast both UVA and UVB protection to limit the adverse effects of the sun on the eyes. Note well! The intensity of the Sun's UV rays can be nearly doubled by snow reflection.
Updated: Jun 11, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

The average high-temperature and low-temperature during December are 45.5°F (7.5°C) and 33.3°F (0.7°C) respectively. In September, the average heat index (a.k.a. 'feels like', 'felt air temperature'), which takes the relative humidity and factors it into the air temperature reading, is estimated at 86°F (30°C).

In Joppa, the average relative humidity in December is 78%.

In Joppa, during December, the rain falls for 11.5 days and regularly aggregates up to 3.03" (77mm) of precipitation.

In Joppa, in December, during 2 snowfall days, 0.47" (12mm) of snow is typically accumulated.

December has the shortest days of the year, with an average of 9h and 42min of daylight.

In Joppa, the average day length in December is 9h and 39min.

On the first day of December, sunrise is at 6:51 am and sunset at 4:38 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 4:48 pm CST.

In Joppa, Illinois, the average sunshine duration in December is 4.9h.

January, February and December, with an average maximum UV index of 2, are months with the lowest UV index.

The average daily maximum UV index in December is 2. A UV Index reading of 2, and below, represents a low health threat from exposure to the Sun's UV radiation.
Average high temperature
Average low temperature
Average pressure
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average snowfall
Average snowfall days
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Joppa, IL

  • Average high temperature in December: 45.5°F

The warmest month (with the highest average high temperature) is July (88.3°F).
The month with the lowest average high temperature is January (41.4°F).

  • Average low temperature in December: 33.3°F

The month with the highest average low temperature is July (68.9°F).
The coldest month (with the lowest average low temperature) is January (28°F).

Average pressure in December
Joppa, IL

  • Average pressure in December: 30.14"Hg

The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.95"Hg).

Average wind speed in December
Joppa, IL

  • Average wind speed in December: 8.3mph

The windiest months (with the highest average wind speed) are January, March and April (8.9mph).
The calmest months (with the lowest average wind speed) are July and August (5.6mph).

Average humidity in December
Joppa, IL

  • Average humidity in December: 78%

The months with the highest relative humidity are March and May (79%).
The month with the lowest relative humidity is October (70%).

Average rainfall in December
Joppa, IL

  • Average rainfall in December: 3.03"

The wettest month (with the highest rainfall) is April (4.29").
The driest month (with the least rainfall) is September (1.5").

Average rainfall days in December
Joppa, IL

  • Average rainfall days in December: 11.5 days

The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is October (10.2 days).

Average snowfall in December
Joppa, IL

  • Average snowfall in December: 0.47"

The month with the highest snowfall is February (1.61").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in December
Joppa, IL

  • Average snowfall days in December: 2 days

The month with the highest number of snowfall days is January (4.3 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).

Average daylight in December /
Average sunshine in December
Joppa, IL

  • Average daylight in December: 9h and 42min

The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).

  • Average sunshine in December: 4h and 54min

The months with the most sunshine are June and July (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 42min).

Average sunshine days in December
Joppa, IL

  • Average sunshine days in December: 17.7 days

The month with the most sunshine days is October (19.3 days).
The month with the least sunshine days is May (11 days).

Average UV index in December
Joppa, IL

  • 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 and December (UV index 2).

Average cloud cover in December
Joppa, IL

  • Average cloud cover in December: 48

The month with the most cloud cover is February (Cloud cover 50).
The month with the least cloud cover is September (Cloud cover 26).

Average visibility in December
Joppa, IL

  • 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).