Contents
- Weather in December
- Frequently asked questions
- Average temperature in December
- Average pressure in December
- Average wind speed in December
- Average humidity in December
- Average rainfall in December
- Average rainfall days in December
- Average snowfall in December
- Average snowfall days in December
- Average daylight in December
- Average sunshine in December
- Average sunshine days in December
- Average UV index in December
- Average cloud cover in December
- Average visibility in December
Weather in December
Temperature
December suggests a modest reduction in the average high-temperature, shifting from a cool 50.9°F (10.5°C) in November to a wintry 39.7°F (4.3°C). In Palmyra, the nighttime temperature averages to a freezing cold 28.6°F (-1.9°C) during December.Humidity
In December, the average relative humidity is 78%.Rainfall
The month with the least rainfall is December, when the rain falls for 8.5 days and typically collects 1.73" (44mm) of precipitation.Snowfall
January through April, November and December are months with snowfall. In December, it is snowing for 4.9 days. Throughout December, 1.69" (43mm) of snow is accumulated. Throughout the year, there are 25.5 snowfall days, and 9.09" (231mm) of snow is accumulated.Daylight
With an average of 9h and 24min of daylight, December has the shortest days of the year.On the first day of the month, sunrise is at 7:01 am and sunset at 4:36 pm. On the last day of December, sunrise is at 7:20 am and sunset at 4:46 pm CST.
Sunshine
In Palmyra, the average sunshine in December is 4.8h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 2. A UV Index value of 2, and less, symbolizes a minimal health hazard from exposure to the Sun's UV radiation for the average person.Note: An average UV index of 2 in December transforms into this advice:
While extended sun exposure does not significantly affect most people, those with sensitive skin, children, and infants should always be protected. Limiting exposure to the direct Sun during midday hours can help prevent harmful UV radiation effects. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage. Beware! The strength of the UV rays is increased nearly double-fold by the reflection of the snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold does it get in December?
What is the average humidity in December?
What is the driest month?
How many days does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
What is the average length of the day in December?
What time are sunrise and sunset in December?
How long on average sun shines in December?
What is the month with the lowest UV index?
What is the UV index intensity in December?
Average temperature in December
Palmyra, IL
- Average high temperature in December: 39.7°F
The warmest month (with the highest average high temperature) is July (83.3°F).
The month with the lowest average high temperature is January (34.2°F).
- Average low temperature in December: 28.6°F
The month with the highest average low temperature is July (66.7°F).
The coldest month (with the lowest average low temperature) is January (22.3°F).
Average pressure in December
Palmyra, IL
- Average pressure in December: 30.13"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in December
Palmyra, IL
- Average wind speed in December: 9.6mph
The windiest month (with the highest average wind speed) is January (10.3mph).
The calmest months (with the lowest average wind speed) are July and August (6mph).
Average humidity in December
Palmyra, IL
- Average humidity in December: 78%
The month with the highest relative humidity is July (82%).
The month with the lowest relative humidity is October (71%).
Average rainfall in December
Palmyra, IL
- Average rainfall in December: 1.73"
The wettest month (with the highest rainfall) is June (3.86").
The driest month (with the least rainfall) is December (1.73").
Average rainfall days in December
Palmyra, IL
- Average rainfall days in December: 8.5 days
The month with the highest number of rainy days is May (17.8 days).
The month with the least rainy days is January (7.4 days).
Average snowfall in December
Palmyra, IL
- Average snowfall in December: 1.69"
The month with the highest snowfall is February (3.19").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in December
Palmyra, IL
- Average snowfall days in December: 4.9 days
The month with the highest number of snowfall days is January (8.5 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
Palmyra, IL
- Average daylight in December: 9h and 2min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 24min).
- Average sunshine in December: 4h and 5min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in December
Palmyra, IL
- Average sunshine days in December: 17.9 days
The month with the most sunshine days is October (18.5 days).
The month with the least sunshine days is May (10.6 days).
Average UV index in December
Palmyra, 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
Palmyra, IL
- Average cloud cover in December: 50
The month with the most cloud cover is January (Cloud cover 53).
The months with the least cloud cover are June, July, August and September (Cloud cover 30).
Average visibility in December
Palmyra, 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).
Palmyra, Illinois, USA
Weather forecast for your location
2. Allow the app to use your location