December weather forecastAltamont, OR
December
Weather in December
The first month of the winter, December, is also an icy month in Altamont, Oregon, with an average temperature varying between 36.9°F (2.7°C) and 25.2°F (-3.8°C).Temperature
December, on average, is the coldest month, registering a high temperature of 36.9°F (2.7°C) and a low of 25.2°F (-3.8°C).Humidity
The average relative humidity in December is 83%.Rainfall
December is the month with the most rainfall. Rain falls for 8.4 days and accumulates 2.09" (53mm) of precipitation.Snowfall
Months with snowfall are January through June, September through December. The month with the most snowfall is December, when snow falls for 13.5 days and typically aggregates up to 10.63" (270mm) of snow.Daylight
December has the shortest days of the year, with an average of 9h and 12min of daylight.On the first day of the month, sunrise is at 7:16 am and sunset at 4:35 pm. On the last day of December, sunrise is at 7:35 am and sunset at 4:45 pm PST.
Sunshine
The average sunshine in December in Altamont is 5.4h.UV index
The average daily maximum UV index in December in Altamont is 2. A UV Index value of 2, and less, symbolizes a low threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum UV index of 2 in December translates into the following recommendations:
Apart from children, who require continuous protection, most can endure sun exposure for up to an hour without experiencing burns. The best time to avoid the Sun's harmful UV radiation is during midday when it's most potent. Experience reduced UV exposure by about half when donning a wide-brim hat. 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
Average temperature in December
Altamont, OR
- Average high temperature in December: 36.9°F
The warmest month (with the highest average high temperature) is July (82°F).
The month with the lowest average high temperature is December (36.9°F).
- Average low temperature in December: 25.2°F
The month with the highest average low temperature is July (48.6°F).
The coldest month (with the lowest average low temperature) is December (25.2°F).
Average pressure in December
Altamont, OR
- Average pressure in December: 30.16"Hg
The month with the highest atmospheric pressure is January (30.18"Hg).
The month with the lowest atmospheric pressure is August (29.96"Hg).
Average wind speed in December
Altamont, OR
- Average wind speed in December: 5.3mph
The windiest months (with the highest average wind speed) are March and April (6.3mph).
The calmest months (with the lowest average wind speed) are August and September (5mph).
Average humidity in December
Altamont, OR
- Average humidity in December: 83%
The month with the highest relative humidity is January (84%).
The month with the lowest relative humidity is August (49%).
Average rainfall in December
Altamont, OR
- Average rainfall in December: 2.09"
The wettest month (with the highest rainfall) is December (2.09").
The driest month (with the least rainfall) is July (0.2").
Average rainfall days in December
Altamont, OR
- Average rainfall days in December: 8.4 days
The month with the highest number of rainy days is April (13.1 days).
The month with the least rainy days is August (3.6 days).
Average snowfall in December
Altamont, OR
- Average snowfall in December: 10.63"
The month with the highest snowfall is December (10.63").
The months with the least snowfall are July and August (0").
Average snowfall days in December
Altamont, OR
- Average snowfall days in December: 13.5 days
The month with the highest number of snowfall days is December (13.5 days).
The months with the least snowfall days are July and August (0 days).
Average daylight in December /
Average sunshine in December
Altamont, OR
- Average daylight in December: 9h and 12min
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: 5h and 24min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is January (Average sunshine: 5h and 18min).
Average sunshine days in December
Altamont, OR
- Average sunshine days in December: 13.6 days
The month with the most sunshine days is August (24.9 days).
The month with the least sunshine days is March (10.6 days).
Average UV index in December
Altamont, OR
- Average UV index in December: 2
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is February (UV index 1).
Average cloud cover in December
Altamont, OR
- Average cloud cover in December: 46
The month with the most cloud cover is December (Cloud cover 46).
The month with the least cloud cover is July (Cloud cover 8).
Average visibility in December
Altamont, OR
- Average visibility in December: 5mi
The months with the highest visibility are April, May, June, July, August, September, October and November (6mi).
The month with the lowest visibility is January (4mi).





