January Weather in Mendham, United States

Last updated: June 24, 2025

In Mendham, United States, the average temperature in January hovers around 0°C (33°F). Temperatures can dip to a chilling -17°C (2°F), while reaching a maximum of 18°C (65°F). Expect about 70 mm (2.7 in) of precipitation spread over 8 days, contributing to the region's average humidity of 84%.

January Temperature in Mendham

In January in Mendham, the average temperature is 0°C (33°F). Maximums can reach 18°C (65°F), while minimums can drop as low as -17°C (2°F). It's essential to pack layers and be prepared for fluctuating temperatures while exploring the beautiful surroundings.

January Weather in Mendham: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Mendham, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Mendham, January typically has an average temperature of 0°C (33°F), with highs reaching up to 18°C (65°F) and lows dropping to around -17°C (2°F).

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

January Precipitation in Mendham

In Mendham in January, the precipitation amount is 70 mm (2.7 in) spread over 8 days.

January Precipitation Trends in Mendham

The chart displays monthly precipitation patterns in Mendham, with values for each month alongside January’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how January’s conditions compare to those of other months. In Mendham, January typically receives around 70 mm (2.7 inches) of precipitation spread over approximately 8 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

January Humidity in Mendham

In Mendham in January humidity is 84%. With average temperature 0°C (33°F), this humidity feels like a damp chill that seeps into your bones, making outdoor adventures less enjoyable and travel plans challenging.

January Average Humidity in Mendham

This chart illustrates the average monthly humidity levels in Mendham, with January’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In January, average humidity in Mendham is approximately 84%, offering insight into how humid the weather typically is during this month.

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

January UV Index in Mendham

In Mendham in January, the maximum UV index is 3, which corresponds to a moderate Exposure Category. The time to burn is approximately 30 minutes. For more details on the hourly UV index in Mendham, you can check the information here.

Maximum UV Index Levels in Mendham for January

The chart shows the monthly maximum UV Index (UVI) for Mendham in January, 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 January, the maximum UV index in Mendham typically reaches 3, which falls under the moderate exposure category.

Data source: Mendham January 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 January Weather in Mendham Compares to Other Months

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

This table compares monthly weather conditions in Mendham, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	0°C (33°F)	70 mm (2.7 inches)	84%	moderate
February Weather	2°C (36°F)	104 mm (4.1 inches)	82%	moderate
March Weather	5°C (41°F)	103 mm (4.1 inches)	81%	high
April Weather	11°C (52°F)	116 mm (4.6 inches)	78%	very high
May Weather	16°C (62°F)	135 mm (5.3 inches)	69%	very high
June Weather	21°C (71°F)	106 mm (4.2 inches)	69%	very high
July Weather	25°C (77°F)	142 mm (5.6 inches)	62%	very high
August Weather	24°C (75°F)	136 mm (5.4 inches)	65%	very high
September Weather	20°C (69°F)	101 mm (4.0 inches)	68%	very high
October Weather	15°C (59°F)	142 mm (5.6 inches)	74%	high
November Weather	7°C (44°F)	86 mm (3.4 inches)	82%	moderate
December Weather	3°C (37°F)	113 mm (4.4 inches)	80%	low