December weather forecastGrantsville, UT
December
Weather in December
December, the first month of the winter in Grantsville, is also an icy month, with temperature in the range of an average low of 22.1°F (-5.5°C) and an average high of 33.8°F (1°C).Temperature
December brings a decrease in the average high-temperature, shifting from a chilly 45.9°F (7.7°C) in November to a wintry 33.8°F (1°C). Throughout December, Grantsville's nights cool down to an average of 22.1°F (-5.5°C).Humidity
The average relative humidity in December is 78%.Rainfall
In Grantsville, in December, during 10.6 rainfall days, 1.93" (49mm) of precipitation is typically accumulated. In Grantsville, during the entire year, the rain falls for 137.7 days and collects up to 20.98" (533mm) of precipitation.Snowfall
January through May, October through December are months with snowfall. The month with the most snowfall is December, when snow falls for 12.5 days and typically aggregates up to 9.69" (246mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 18min of daylight.On the first day of December, sunrise is at 7:34 am and sunset at 5:03 pm. On the last day of the month, sunrise is at 7:53 am and sunset at 5:13 pm MST.
Sunshine
In December, the average sunshine is 5.4h.UV index
The month with the lowest UV index is December, with an average maximum UV index of 1. A UV Index reading of 2, and below, represents a minimal health vulnerability from unprotected exposure to Sun's UV rays for the ordinary person.Note: In December, a regular UV index of 1 translates into these guidelines:
Many can withstand an hour in the sun without burning, yet children must always have protection against sunlight. The intensity of the Sun's UV radiation during midday suggests reducing time spent outdoors. On sunny days, it's ideal to wear sunglasses that filter out UVA and UVB rays. Be cautious! The UV radiation from the Sun can be magnified almost twofold by snow reflection.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Grantsville, UT
- Average high temperature in December: 33.8°F
The warmest month (with the highest average high temperature) is July (84.2°F).
The month with the lowest average high temperature is January (33.4°F).
- Average low temperature in December: 22.1°F
The month with the highest average low temperature is July (63.5°F).
The coldest month (with the lowest average low temperature) is January (21.2°F).
Average pressure in December
Grantsville, UT
- Average pressure in December: 30.22"Hg
The month with the highest atmospheric pressure is January (30.27"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in December
Grantsville, UT
- Average wind speed in December: 7.1mph
The windiest month (with the highest average wind speed) is March (8.1mph).
The calmest month (with the lowest average wind speed) is January (6mph).
Average humidity in December
Grantsville, UT
- Average humidity in December: 78%
The month with the highest relative humidity is January (83%).
The month with the lowest relative humidity is July (36%).
Average rainfall in December
Grantsville, UT
- Average rainfall in December: 1.93"
The wettest month (with the highest rainfall) is April (2.52").
The driest month (with the least rainfall) is June (1.1").
Average rainfall days in December
Grantsville, UT
- Average rainfall days in December: 10.6 days
The month with the highest number of rainy days is April (16.3 days).
The month with the least rainy days is November (7.5 days).
Average snowfall in December
Grantsville, UT
- Average snowfall in December: 9.69"
The month with the highest snowfall is December (9.69").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in December
Grantsville, UT
- Average snowfall days in December: 12.5 days
The month with the highest number of snowfall days is December (12.5 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in December /
Average sunshine in December
Grantsville, UT
- Average daylight in December: 9h and 18min
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 18min).
- Average sunshine in December: 5h and 24min
The month with the most sunshine is August (Average sunshine: 11h and 48min).
The month with the least sunshine is January (Average sunshine: 5h and 6min).
Average sunshine days in December
Grantsville, UT
- Average sunshine days in December: 13.1 days
The month with the most sunshine days is October (19.5 days).
The month with the least sunshine days is February (10.2 days).
Average UV index in December
Grantsville, UT
- Average UV index in December: 1
The months with the highest UV index are June, July and August (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover in December
Grantsville, UT
- Average cloud cover in December: 43
The month with the most cloud cover is January (Cloud cover 45).
The month with the least cloud cover is August (Cloud cover 13).
Average visibility in December
Grantsville, UT
- Average visibility in December: 6mi
The months with the highest visibility are March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January and February (5mi).
