December weather forecastSan Luis, AZ
December
Weather in December
December in San Luis, Arizona marks the end of the year with the one of the lowest average high temperatures at 67.1°F (19.5°C); a drastic shift from the sweltering summer heat. Shifting wind patterns and reduced daylight hours complement these decreased temperatures. Minimal precipitation and lower relative humidity keep the climatic conditions relatively dry. As the city transitions into winter, December's cold and short days make it a perfect period for indoor activities and festive preparations.Temperature
December, marked by an average high-temperature of 67.1°F (19.5°C) and a low-temperature of 50.5°F (10.3°C), is the coldest month.Humidity
December is the most humid month, with an average relative humidity of 38%.Rainfall
In December, the rain falls for 2 days. Throughout December, 0.24" (6mm) of precipitation is accumulated. Throughout the year, there are 25 rainfall days, and 2.24" (57mm) of precipitation is accumulated.Daylight
December has the shortest days of the year, with an average of 10h and 6min of daylight.On the first day of the month, sunrise is at 7:23 am and sunset at 5:33 pm. On the last day of December, sunrise is at 7:40 am and sunset at 5:44 pm MST.
Sunshine
December has the least sunshine of the year in San Luis, with an average of 7.1h of sunshine.UV index
December is the month with the lowest UV index, with an average maximum UV index of 4. A UV Index reading of 3 to 5 represents a moderate health risk from unsafe exposure to UV radiation for average individuals.Note: A maximum high UV index of 4 in December translates into the following recommendations:
Preventative actions are necessary - The mandate to avoid skin and eye damage is in place. Sun's radiation is most powerful around mid-day, so it's best to limit outdoor activities during this time. On days when the sun blazes, arm yourself with sunglasses that block UVA and UVB radiation.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in December
San Luis, AZ
- Average high temperature in December: 67.1°F
The warmest month (with the highest average high temperature) is July (106.2°F).
The month with the lowest average high temperature is December (67.1°F).
- Average low temperature in December: 50.5°F
The month with the highest average low temperature is August (86.2°F).
The coldest month (with the lowest average low temperature) is December (50.5°F).
Average pressure in December
San Luis, AZ
- Average pressure in December: 30.04"Hg
The month with the highest atmospheric pressure is January (30.07"Hg).
The month with the lowest atmospheric pressure is June (29.75"Hg).
Average wind speed in December
San Luis, AZ
- Average wind speed in December: 7.1mph
The windiest month (with the highest average wind speed) is July (8.5mph).
The calmest month (with the lowest average wind speed) is November (6.7mph).
Average humidity in December
San Luis, AZ
- Average humidity in December: 38%
The month with the highest relative humidity is December (38%).
The month with the lowest relative humidity is June (23%).
Average rainfall in December
San Luis, AZ
- Average rainfall in December: 0.24"
The wettest month (with the highest rainfall) is July (0.39").
The driest month (with the least rainfall) is May (0").
Average rainfall days in December
San Luis, AZ
- Average rainfall days in December: 2 days
The month with the highest number of rainy days is July (5.1 days).
The month with the least rainy days is May (0.3 days).
Average daylight in December /
Average sunshine in December
San Luis, AZ
- Average daylight in December: 10h and 6min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 6min).
- Average sunshine in December: 7h and 6min
The months with the most sunshine are June and July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 7h and 6min).
Average sunshine days in December
San Luis, AZ
- Average sunshine days in December: 28.7 days
The month with the most sunshine days is May (30.4 days).
The month with the least sunshine days is July (24.3 days).
Average UV index in December
San Luis, AZ
- Average UV index in December: 4
The months with the highest UV index are June, July, August and September (UV index 8).
The month with the lowest UV index is December (UV index 4).
Average cloud cover in December
San Luis, AZ
- Average cloud cover in December: 18
The month with the most cloud cover is December (Cloud cover 18).
The month with the least cloud cover is June (Cloud cover 5).
Average visibility in December
San Luis, 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).
