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
A shift in Gary's weather is noticeable as November turns into December, with the average high temperature decreasing from a cold 41.4°F (5.2°C) to a freezing cold 25.3°F (-3.7°C). December is noted for a mean low-temperature of 14°F (-10°C).Humidity
The average relative humidity in December is 85%.Rainfall
In Gary, in December, during 3 rainfall days, 0.67" (17mm) of precipitation is typically accumulated. Throughout the year, there are 101.9 rainfall days, and 14.61" (371mm) of precipitation is accumulated.Snowfall
January through May, October through December are months with snowfall. In Gary, in December, snow falls for 10.9 days, with typically accumulated 3.15" (80mm) of snow. In Gary, South Dakota, during the entire year, snow falls for 49.9 days and aggregates up to 14.02" (356mm) of snow.Daylight
The month with the shortest days is December, with an average of 8h and 54min of daylight.On the first day of the month, sunrise is at 7:43 am and sunset at 4:46 pm. On the last day of December, sunrise is at 8:03 am and sunset at 4:55 pm CST.
Sunshine
In December, the average sunshine is 4.3h.UV index
In December, the average daily maximum UV index in Gary is 2. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV rays for ordinary individuals.Note: A maximum UV index of 2 in December translates into the following recommendations:
While extended sun exposure does not significantly affect most people, those with sensitive skin, children, and infants should always be protected. UV radiation is strongest from the Sun during midday; protect yourself by staying in shaded areas. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance. Be mindful! The reflection from snow can increase the Sun's UV radiation nearly twice.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How cold is December?
What is the average humidity in December?
How many days does it rain in December?
How many days does it snow in December?
What is the month with the shortest days?
How many hours of daylight does Gary have in December?
What time are sunrise and sunset in December?
How long on average sun shines in December?
What is the UV index reading in December in Gary?
Average temperature in December
Gary, SD
- Average high temperature in December: 25.3°F
The warmest month (with the highest average high temperature) is July (81.1°F).
The month with the lowest average high temperature is January (20.5°F).
- Average low temperature in December: 14°F
The month with the highest average low temperature is July (62.1°F).
The coldest month (with the lowest average low temperature) is January (7.2°F).
Average pressure in December
Gary, SD
- Average pressure in December: 30.12"Hg
The months with the highest atmospheric pressure are January and February (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in December
Gary, SD
- Average wind speed in December: 10.5mph
The windiest month (with the highest average wind speed) is April (10.9mph).
The calmest month (with the lowest average wind speed) is July (8mph).
Average humidity in December
Gary, SD
- Average humidity in December: 85%
The month with the highest relative humidity is January (89%).
The month with the lowest relative humidity is October (67%).
Average rainfall in December
Gary, SD
- Average rainfall in December: 0.67"
The wettest month (with the highest rainfall) is July (2.56").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days in December
Gary, SD
- Average rainfall days in December: 3 days
The month with the highest number of rainy days is June (16.5 days).
The month with the least rainy days is January (1.7 days).
Average snowfall in December
Gary, SD
- Average snowfall in December: 3.15"
The month with the highest snowfall is February (3.27").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Gary, SD
- Average snowfall days in December: 10.9 days
The month with the highest number of snowfall days is January (11.3 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Gary, SD
- Average daylight in December: 8h and 5min
The month with the longest days is June (Average daylight: 15h and 30min).
The month with the shortest days is December (Average daylight: 8h and 54min).
- Average sunshine in December: 4h and 2min
The month with the most sunshine is July (Average sunshine: 10h and 36min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days in December
Gary, SD
- Average sunshine days in December: 19.8 days
The month with the most sunshine days is November (21.5 days).
The month with the least sunshine days is June (11.3 days).
Average UV index in December
Gary, SD
- Average UV index in December: 2
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and November (UV index 1).
Average cloud cover in December
Gary, SD
- Average cloud cover in December: 55
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 26).
Average visibility in December
Gary, SD
- Average visibility in December: 6mi
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (6mi).
The month with the lowest visibility is January (5mi).
Gary, South Dakota, USA
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