January Weather in Merrimack, United States

Last updated: June 24, 2025

In January, the average temperature in Merrimack, United States hovers around -2°C (29°F). However, temperatures can vary significantly, with a minimum of -22°C (-7°F) and a maximum of 19°C (67°F). Expect 71 mm (2.8 in) of precipitation over approximately 8 days, and be prepared for a high average humidity of 86%, making for a chilly and damp atmosphere.

January Temperature in Merrimack

In January in Merrimack, the average temperature is -2°C (29°F). Maximum temperatures can reach 19°C (67°F), while the minimum can drop as low as -22°C (-7°F). Be sure to pack layers and prepare for a wide range of temperatures when traveling during this time.

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

The chart illustrates January temperature patterns in Merrimack, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Merrimack, January typically has an average temperature of -2°C (29°F), with highs reaching up to 19°C (67°F) and lows dropping to around -22°C (-7°F).

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

January Precipitation in Merrimack

In Merrimack in January, the precipitation amount is 71 mm (2.8 in) over the course of 8 days.

January Precipitation Trends in Merrimack

The chart displays monthly precipitation patterns in Merrimack, 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 Merrimack, January typically receives around 71 mm (2.8 inches) of precipitation spread over approximately 8 days.

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

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Millimeters (mm) Inches (in)

January Humidity in Merrimack

In Merrimack in January humidity is 86%. With an average temperature of -2°C (29°F), this humidity feels like a damp chill that seeps through layers of clothing, making outdoor activities uncomfortable and travel plans challenging.

January Average Humidity in Merrimack

This chart illustrates the average monthly humidity levels in Merrimack, 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 Merrimack is approximately 86%, 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 Merrimack

In Merrimack 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 Merrimack, you can check the information here.

Maximum UV Index Levels in Merrimack for January

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

Data source: Merrimack 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 Merrimack Compares to Other Months

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

This table compares monthly weather conditions in Merrimack, showing how January’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-2°C (29°F)	71 mm (2.8 inches)	86%	moderate
February Weather	-1°C (31°F)	84 mm (3.3 inches)	84%	moderate
March Weather	2°C (37°F)	82 mm (3.2 inches)	82%	moderate
April Weather	9°C (48°F)	126 mm (5.0 inches)	80%	very high
May Weather	15°C (59°F)	81 mm (3.2 inches)	72%	very high
June Weather	20°C (69°F)	85 mm (3.3 inches)	72%	very high
July Weather	23°C (74°F)	136 mm (5.4 inches)	67%	very high
August Weather	23°C (73°F)	85 mm (3.4 inches)	66%	very high
September Weather	19°C (66°F)	77 mm (3.0 inches)	71%	high
October Weather	12°C (55°F)	128 mm (5.0 inches)	78%	high
November Weather	5°C (41°F)	98 mm (3.9 inches)	84%	moderate
December Weather	0°C (32°F)	120 mm (4.7 inches)	81%	low