December weather forecastPenfield, IL

December

Weather in December

December, the first month of the winter in Penfield, is also an icy month, with an average temperature fluctuating between 27.5°F (-2.5°C) and 37.6°F (3.1°C).

Temperature

The arrival of December corresponds with a reduction in the average high-temperature, down from November's chilly 48.7°F (9.3°C) to an icy 37.6°F (3.1°C). Penfield experiences an average low-temperature of 27.5°F (-2.5°C) in the month of December.

Humidity

The average relative humidity in December is 80%.

Rainfall

In Penfield, in December, during 6.9 rainfall days, 0.71" (18mm) of precipitation is typically accumulated. Throughout the year, there are 121.5 rainfall days, and 13.46" (342mm) of precipitation is accumulated.

Snowfall

Months with snowfall in Penfield are January through April, November and December. In Penfield, in December, snow falls for 6.1 days, with typically accumulated 0.83" (21mm) of snow. Throughout the year, in Penfield, there are 26.9 snowfall days, and 3.78" (96mm) of snow is accumulated.

Daylight

With an average of 9h and 24min of daylight, December has the shortest days of the year in Penfield.
On the first day of December in Penfield, sunrise is at 6:55 am and sunset at 4:26 pm. On the last day of the month, sunrise is at 7:14 am and sunset at 4:35 pm CST.

Sunshine

In December, the average sunshine is 4.5h.

UV index

January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index. A UV Index estimate of 2, and below, represents a low health risk from unprotected exposure to Sun's UV rays for average individuals.
Note: In December, the maximum UV index of 2 suggests this advice:
Though the majority can handle prolonged sun exposure, it is crucial to always shield babies, children, and those with fair skin. To prevent harmful UV exposure, minimize direct contact with the Sun around midday. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days. Be mindful! The reflection from snow can increase the Sun's UV radiation nearly twice.
Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

The high-temperature, in December, in Penfield, is 37.6°F (3.1°C), while the low-temperature averages to 27.5°F (-2.5°C). The average heat index (a.k.a. 'feels like', 'apparent temperature'), which represents the influence of relative humidity on air temperature, in July is evaluated at 87.8°F (31°C).

In Penfield, Illinois, the average relative humidity in December is 80%.

In December, in Penfield, the rain falls for 6.9 days. Throughout December, 0.71" (18mm) of precipitation is accumulated.

In Penfield, during December, snow falls for 6.1 days and regularly aggregates up to 0.83" (21mm) of snow.

December has the shortest days of the year, with an average of 9h and 24min of daylight.

The average day length in December is 9h and 22min.

On the first day of December in Penfield, Illinois, sunrise is at 6:55 am and sunset at 4:26 pm. On the last day of the month, sunrise is at 7:14 am and sunset at 4:35 pm CST.

The average sunshine duration in December in Penfield, Illinois, is 4.5h.

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

In Penfield, the average daily maximum UV index in December is 2. A UV Index of 2, and less, symbolizes a minimal hazard to health from exposure to Sun's UV rays.
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 daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in December
Penfield, IL

  • Average high temperature in December: 37.6°F

The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (31.5°F).

  • Average low temperature in December: 27.5°F

The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (19.8°F).

Average pressure in December
Penfield, IL

  • Average pressure in December: 30.12"Hg

The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

Average wind speed in December
Penfield, IL

  • Average wind speed in December: 10.1mph

The windiest month (with the highest average wind speed) is January (10.7mph).
The calmest month (with the lowest average wind speed) is August (6.4mph).

Average humidity in December
Penfield, IL

  • Average humidity in December: 80%

The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (71%).

Average rainfall in December
Penfield, IL

  • Average rainfall in December: 0.71"

The wettest month (with the highest rainfall) is May (1.77").
The driest month (with the least rainfall) is February (0.67").

Average rainfall days in December
Penfield, IL

  • Average rainfall days in December: 6.9 days

The month with the highest number of rainy days is May (14.8 days).
The month with the least rainy days is February (4.6 days).

Average snowfall in December
Penfield, IL

  • Average snowfall in December: 0.83"

The month with the highest snowfall is February (1.38").
The months with the least snowfall are May, June, July, August, September and October (0").

Average snowfall days in December
Penfield, IL

  • Average snowfall days in December: 6.1 days

The month with the highest number of snowfall days is January (7.9 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
Penfield, IL

  • Average daylight in December: 9h and 24min

The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 24min).

  • Average sunshine in December: 4h and 30min

The month with the most sunshine is June (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).

Average sunshine days in December
Penfield, IL

  • Average sunshine days in December: 19.4 days

The month with the most sunshine days is November (20.4 days).
The month with the least sunshine days is July (11.3 days).

Average UV index in December
Penfield, IL

  • Average UV index in December: 2

The months with the highest UV index are 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
Penfield, IL

  • Average cloud cover in December: 54

The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 31).

Average visibility in December
Penfield, IL

  • Average visibility in December: 6mi

The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).