December Weather in Monticello, United States

Last updated: June 24, 2025

In Monticello, United States, the average temperature in December hovers around 10°C (51°F). Expect cool days where the minimum can drop to -4°C (24°F), while warm spells might see temperatures rise to a pleasant 25°C (78°F). With an average precipitation of 133 mm (5.2 in) spread over 11 days, and a high humidity level of 89%, be prepared for a mix of weather.

December Temperature in Monticello

In December in Monticello, the average temperature is 10°C (51°F), with maximums reaching 25°C (78°F) and minimums dipping as low as -4°C (24°F). This range makes it important for travelers to pack for both warm and cool conditions, ensuring comfort for various outdoor activities.

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

The chart illustrates December temperature patterns in Monticello, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Monticello, December typically has an average temperature of 10°C (51°F), with highs reaching up to 25°C (78°F) and lows dropping to around -4°C (24°F).

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

December Precipitation in Monticello

In Monticello in December, the precipitation amount is 133 mm (5.2 in) spread over a period of 11 days.

December Precipitation Trends in Monticello

The chart displays monthly precipitation patterns in Monticello, 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 Monticello, December typically receives around 133 mm (5.2 inches) of precipitation spread over approximately 11 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

December Humidity in Monticello

In Monticello in December humidity is 89%. With an average temperature of 10°C (51°F), this humidity feels like traveling through a thick fog, where the damp air clings to your skin, making the coolness feel even chillier and adding an element of discomfort to your adventures.

December Average Humidity in Monticello

This chart illustrates the average monthly humidity levels in Monticello, 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 Monticello is approximately 89%, 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 Monticello

In Monticello 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 Monticello for better planning.

Maximum UV Index Levels in Monticello for December

The chart shows the monthly maximum UV Index (UVI) for Monticello 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 Monticello typically reaches 4, which falls under the moderate exposure category.

Data source: Monticello 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 Monticello Compares to Other Months

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

This table compares monthly weather conditions in Monticello, showing how December’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	9°C (48°F)	106 mm (4.2 inches)	86%	moderate
February Weather	12°C (54°F)	127 mm (5.0 inches)	84%	high
March Weather	15°C (59°F)	88 mm (3.5 inches)	83%	very high
April Weather	18°C (65°F)	103 mm (4.0 inches)	81%	very high
May Weather	23°C (73°F)	95 mm (3.7 inches)	81%	extreme
June Weather	26°C (78°F)	119 mm (4.7 inches)	81%	extreme
July Weather	27°C (81°F)	116 mm (4.6 inches)	83%	extreme
August Weather	27°C (80°F)	123 mm (4.9 inches)	81%	very high
September Weather	25°C (77°F)	103 mm (4.1 inches)	82%	very high
October Weather	20°C (68°F)	107 mm (4.2 inches)	78%	very high
November Weather	13°C (55°F)	79 mm (3.1 inches)	86%	high
December Weather	10°C (51°F)	133 mm (5.2 inches)	89%	moderate