December Weather in Alto, United States

Last updated: June 24, 2025

In December, the average temperature in Alto, United States hovers around 12°C (54°F). While the temperatures can drop to a chilly -4°C (26°F), they can also reach a warm 28°C (83°F). Expect 116 mm (4.6 in) of precipitation spread over 9 days, accompanied by a high average humidity of 87%. Prepare accordingly!

December Temperature in Alto

In December in Alto, the average temperature is 12°C (54°F), with maximums reaching 28°C (83°F) and minimums dropping as low as -4°C (26°F). Be prepared for a wide range of weather conditions when traveling during this time, making it essential to pack layers for your trip.

December Weather in Alto: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Alto, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Alto, December typically has an average temperature of 12°C (54°F), with highs reaching up to 28°C (83°F) and lows dropping to around -4°C (26°F).

Data source: Temperature data for Alto generated using information from the Copernicus Climate Change Service.

December Precipitation in Alto

In Alto in December, the precipitation amount is 116 mm (4.6 in) spread over 9 days.

December Precipitation Trends in Alto

The chart displays monthly precipitation patterns in Alto, with values for each month alongside December’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December’s conditions compare to those of other months. In Alto, December typically receives around 116 mm (4.6 inches) of precipitation spread over approximately 9 days.

Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

December Humidity in Alto

In Alto in December humidity is 87%. With an average temperature of 12°C (54°F), this humidity feels like a damp embrace, making it quite uncomfortable for traveling, as the air feels heavy and can quickly sap your energy as you explore the sights.

December Average Humidity in Alto

This chart illustrates the average monthly humidity levels in Alto, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in Alto is approximately 87%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Alto

In Alto in December, the maximum UV index reaches 4, which corresponds to a moderate Exposure Category. With a time to burn of 30 minutes, it’s important to take precautions to protect your skin. You can find more details in the Hourly UV Index in Alto for better planning.

Maximum UV Index Levels in Alto for December

The chart shows the monthly maximum UV Index (UVI) for Alto in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In December, the maximum UV index in Alto typically reaches 4, which falls under the moderate exposure category.

Data source: Alto December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How December Weather in Alto Compares to Other Months

Weather in Alto varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Alto, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Alto, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	10°C (50°F)	101 mm (4.0 inches)	79%	moderate
February Weather	11°C (53°F)	135 mm (5.3 inches)	80%	high
March Weather	16°C (62°F)	115 mm (4.5 inches)	78%	very high
April Weather	19°C (66°F)	142 mm (5.6 inches)	79%	extreme
May Weather	24°C (75°F)	145 mm (5.7 inches)	81%	extreme
June Weather	27°C (81°F)	111 mm (4.4 inches)	77%	extreme
July Weather	29°C (84°F)	80 mm (3.2 inches)	71%	extreme
August Weather	29°C (85°F)	102 mm (4.0 inches)	67%	extreme
September Weather	26°C (80°F)	97 mm (3.8 inches)	69%	very high
October Weather	21°C (70°F)	121 mm (4.8 inches)	73%	very high
November Weather	14°C (58°F)	76 mm (3.0 inches)	82%	high
December Weather	12°C (54°F)	116 mm (4.6 inches)	87%	moderate