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
Alton's temperature records reveal December as the coldest month, marked by average highs of 25.2°F (-3.8°C) and lows of 9.5°F (-12.5°C).Humidity
The average relative humidity in December is 89%.Rainfall
In December, the rain falls for 8.5 days. Throughout December, 1.89" (48mm) of precipitation is accumulated. In Alton, during the entire year, the rain falls for 117.5 days and collects up to 20.24" (514mm) of precipitation.Snowfall
Months with snowfall are January through June, September through December. In December, in Alton, it is snowing for 21.6 days. Throughout December, 14.49" (368mm) of snow is accumulated. Throughout the year, there are 116.1 snowfall days, and 91.14" (2315mm) of snow is accumulated.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of December, sunrise is at 7:34 am and sunset at 4:53 pm. On the last day of the month, sunrise is at 7:53 am and sunset at 5:02 pm MST.
Sunshine
In December, the average sunshine is 4.7h.UV index
January, November and December, with an average maximum UV index of 1, are months with the lowest UV index. A UV Index of 2, and less, symbolizes a minimal health hazard from unsafe exposure to UV radiation for the ordinary person.Note: The maximum UV index, 1 during December, leads to the following recommendations:
Protection from prolonged sun exposure is necessary for babies, children, and individuals with sensitive skin. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. Equip yourself with UVA and UVB-filtering sunglasses on clear, sunny days. Be vigilant! The reflective nature of snow can increase the Sun's UV radiation nearly twofold.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the coldest months?
How cold is it in December?
What is the average humidity in December in Alton?
How many days does it rain in December?
How many days does it snow in December in Alton?
What is the month with the shortest days?
How many hours of daylight does Alton have in December?
What time are sunrise and sunset in December?
How long on average sun shines in December?
What are the months with the lowest UV index?
How high is the UV index in December?
Average temperature in December
Alton, ID
- Average high temperature in December: 25.2°F
The warmest month (with the highest average high temperature) is July (79°F).
The month with the lowest average high temperature is December (25.2°F).
- Average low temperature in December: 9.5°F
The month with the highest average low temperature is July (48.9°F).
The coldest month (with the lowest average low temperature) is January (7.9°F).
Average pressure in December
Alton, ID
- Average pressure in December: 30.25"Hg
The month with the highest atmospheric pressure is January (30.29"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed in December
Alton, ID
- Average wind speed in December: 4.2mph
The windiest month (with the highest average wind speed) is June (5.8mph).
The calmest months (with the lowest average wind speed) are January and December (4.2mph).
Average humidity in December
Alton, ID
- Average humidity in December: 89%
The months with the highest relative humidity are January and February (92%).
The month with the lowest relative humidity is August (42%).
Average rainfall in December
Alton, ID
- Average rainfall in December: 1.89"
The wettest month (with the highest rainfall) is May (2.6").
The driest month (with the least rainfall) is July (0.63").
Average rainfall days in December
Alton, ID
- Average rainfall days in December: 8.5 days
The month with the highest number of rainy days is May (17.3 days).
The month with the least rainy days is January (6 days).
Average snowfall in December
Alton, ID
- Average snowfall in December: 14.49"
The month with the highest snowfall is February (18.39").
The months with the least snowfall are July and August (0").
Average snowfall days in December
Alton, ID
- Average snowfall days in December: 21.6 days
The month with the highest number of snowfall days is December (21.6 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in December /
Average sunshine in December
Alton, ID
- Average daylight in December: 9h and 1min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in December: 4h and 4min
The month with the most sunshine is July (Average sunshine: 11h and 54min).
The month with the least sunshine is January (Average sunshine: 4h and 24min).
Average sunshine days in December
Alton, ID
- Average sunshine days in December: 9.4 days
The month with the most sunshine days is July (18.8 days).
The month with the least sunshine days is February (6.8 days).
Average UV index in December
Alton, ID
- Average UV index in December: 1
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, November and December (UV index 1).
Average cloud cover in December
Alton, ID
- Average cloud cover in December: 55
The month with the most cloud cover is February (Cloud cover 62).
The months with the least cloud cover are July and August (Cloud cover 12).
Average visibility in December
Alton, ID
- Average visibility in December: 4mi
The months with the highest visibility are May, June, July, August, September and October (6mi).
The months with the lowest visibility are January and February (3mi).
Alton, Idaho, USA
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