December Weather in Morristown, United States

Last updated: June 24, 2025

In December, the average temperature in Morristown, United States hovers around -4°C (25°F). While you might experience chilling lows of -25°C (-12°F), temperatures can peak at a mild 17°C (63°F). Expect about 46 mm (1.8 in) of precipitation spread over 6 days, coupled with a high average humidity of 84%. Be prepared for a mix of weather!

December Temperature in Morristown

In December in Morristown, the average temperature is -4°C (25°F), with maximums reaching 17°C (63°F) and minimums dropping as low as -25°C (-12°F). It's essential to pack for a wide range of temperatures and be prepared for cold weather while traveling during this time.

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

The chart illustrates December temperature patterns in Morristown, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Morristown, December typically has an average temperature of -4°C (25°F), with highs reaching up to 17°C (63°F) and lows dropping to around -25°C (-12°F).

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

December Precipitation in Morristown

In Morristown in December, the precipitation amount is 46 mm (1.8 in) over a span of 6 days.

December Precipitation Trends in Morristown

The chart displays monthly precipitation patterns in Morristown, 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 Morristown, December typically receives around 46 mm (1.8 inches) of precipitation spread over approximately 6 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 Morristown

In Morristown in December, humidity is 84%. With an average temperature of -4°C (25°F), this humidity feels like a biting chill that seeps into your bones, making outdoor activities uncomfortable and travel less enjoyable.

December Average Humidity in Morristown

This chart illustrates the average monthly humidity levels in Morristown, 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 Morristown is approximately 84%, 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 Morristown

In Morristown in December, the maximum UV index is 2, which corresponds to a low exposure category. With this level of UV radiation, the time to burn is approximately 45 minutes. To learn more about the hourly UV index in Morristown, you can visit Hourly UV Index in Morristown.

Maximum UV Index Levels in Morristown for December

The chart shows the monthly maximum UV Index (UVI) for Morristown 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 Morristown typically reaches 2, which falls under the low exposure category.

Data source: Morristown 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 Morristown Compares to Other Months

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

This table compares monthly weather conditions in Morristown, 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 (17°F)	35 mm (1.4 inches)	87%	moderate
February Weather	-9°C (17°F)	39 mm (1.5 inches)	90%	moderate
March Weather	1°C (33°F)	65 mm (2.6 inches)	85%	moderate
April Weather	6°C (44°F)	89 mm (3.5 inches)	84%	very high
May Weather	15°C (59°F)	136 mm (5.3 inches)	78%	very high
June Weather	22°C (72°F)	114 mm (4.5 inches)	80%	very high
July Weather	23°C (74°F)	112 mm (4.4 inches)	81%	very high
August Weather	21°C (71°F)	136 mm (5.3 inches)	81%	very high
September Weather	18°C (65°F)	139 mm (5.5 inches)	81%	very high
October Weather	9°C (49°F)	91 mm (3.6 inches)	84%	moderate
November Weather	1°C (34°F)	37 mm (1.5 inches)	88%	moderate
December Weather	-4°C (25°F)	46 mm (1.8 inches)	84%	low