December weather forecastPortal, AZ
December
Weather in December
December marks the arrival of winter in Portal, Arizona. With a considerable drop in temperature from November, it is the coldest month of the year. Although the number of daylight hours is at the lowest, the amount of sunshine doesn't decrease by as steep a margin, allowing for bright winter days. A unique feature of December is a significant occurrence of snowfall at around 0.79" (20mm) after being almost absent for most of the year. As the year ends, the city gears up for winter, with brisk winds and cooler temperatures enveloping the landscape.Temperature
December is the coldest month, exhibiting average temperatures of 54.5°F (12.5°C) at the peak and 37.6°F (3.1°C) at the base.Humidity
December is the most humid month, with an average relative humidity of 51%.Rainfall
In Portal, during December, the rain falls for 5.2 days and regularly aggregates up to 0.55" (14mm) of precipitation. Throughout the year, there are 73.4 rainfall days, and 7.91" (201mm) of precipitation is accumulated.Snowfall
January through March, November and December are months with snowfall. December is the month with the most snowfall. Snow falls for 1.5 days and accumulates 0.79" (20mm) of snow.Daylight
The month with the shortest days is December, with an average of 10h and 6min of daylight.On the first day of the month, sunrise is at 6:59 am and sunset at 5:12 pm. On the last day of December, sunrise is at 7:16 am and sunset at 5:23 pm MST.
Sunshine
December has the least sunshine of the year in Portal, with an average of 7h of sunshine.UV index
The month with the lowest UV index is December, with an average maximum UV index of 2. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV radiation for the average person.Note: In December, an average UV index of 2 transforms into the following instructions:
Protection from prolonged sun exposure is necessary for babies, children, and individuals with sensitive skin. Avoiding the Sun during its peak radiation time around midday is a healthy practice. Loose clothes with a tight weave are optimal for safeguarding yourself against the Sun's rays. Notice! The UV radiation of the Sun can be intensified nearly twofold due to the reflective quality of snow.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
Portal, AZ
- Average high temperature in December: 54.5°F
The warmest month (with the highest average high temperature) is June (92.8°F).
The month with the lowest average high temperature is December (54.5°F).
- Average low temperature in December: 37.6°F
The month with the highest average low temperature is July (73°F).
The coldest month (with the lowest average low temperature) is January (36.3°F).
Average pressure in December
Portal, AZ
- Average pressure in December: 30.07"Hg
The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in December
Portal, AZ
- Average wind speed in December: 7.4mph
The windiest month (with the highest average wind speed) is April (11.1mph).
The calmest month (with the lowest average wind speed) is January (7.1mph).
Average humidity in December
Portal, AZ
- Average humidity in December: 51%
The month with the highest relative humidity is December (51%).
The month with the lowest relative humidity is May (21%).
Average rainfall in December
Portal, AZ
- Average rainfall in December: 0.55"
The wettest month (with the highest rainfall) is July (1.81").
The driest month (with the least rainfall) is April (0.12").
Average rainfall days in December
Portal, AZ
- Average rainfall days in December: 5.2 days
The month with the highest number of rainy days is July (15 days).
The month with the least rainy days is May (2.1 days).
Average snowfall in December
Portal, AZ
- Average snowfall in December: 0.79"
The month with the highest snowfall is December (0.79").
The months with the least snowfall are April, May, June, July, August, September and October (0").
Average snowfall days in December
Portal, AZ
- Average snowfall days in December: 1.5 days
The month with the highest number of snowfall days is December (1.5 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in December /
Average sunshine in December
Portal, AZ
- Average daylight in December: 10h and 6min
The month with the longest days is June (Average daylight: 14h and 12min).
The month with the shortest days is December (Average daylight: 10h and 6min).
- Average sunshine in December: 7h and 0min
The month with the most sunshine is June (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 7h and 0min).
Average sunshine days in December
Portal, AZ
- Average sunshine days in December: 25.1 days
The month with the most sunshine days is May (28.5 days).
The month with the least sunshine days is July (9.9 days).
Average UV index in December
Portal, AZ
- Average UV index in December: 2
The months with the highest UV index are May, June, July and August (UV index 7).
The month with the lowest UV index is December (UV index 2).
Average cloud cover in December
Portal, AZ
- Average cloud cover in December: 20
The months with the most cloud cover are July and December (Cloud cover 20).
The month with the least cloud cover is May (Cloud cover 8).
Average visibility in December
Portal, AZ
- Average visibility in December: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
