January Weather in Saint Marys, United States

Last updated: June 24, 2025

In January, the average temperature in Saint Marys, United States hovers around -2°C (30°F). You can expect minimum temperatures to plunge as low as -25°C (-13°F), while the highs can reach a mild 18°C (65°F). This month usually brings about 74 mm (2.9 in) of precipitation over 9 days, and with an average humidity level of 88%, be prepared for a moist and chilly atmosphere!

January Temperature in Saint Marys

In January in Saint Marys, the average temperature is -2°C (30°F), with maximums reaching 18°C (65°F) and minimums dropping as low as -25°C (-13°F). Be prepared for a wide range of temperatures when traveling to Saint Marys during this time.

January Weather in Saint Marys: Daily Temperature Highs, Lows, and Averages

The chart illustrates January temperature patterns in Saint Marys, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Saint Marys, January typically has an average temperature of -2°C (30°F), with highs reaching up to 18°C (65°F) and lows dropping to around -25°C (-13°F).

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

January Precipitation in Saint Marys

In Saint Marys in January, the precipitation amount is 74 mm (2.9 in), which occurs over a span of 9 days.

January Precipitation Trends in Saint Marys

The chart displays monthly precipitation patterns in Saint Marys, 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 Saint Marys, January typically receives around 74 mm (2.9 inches) of precipitation spread over approximately 9 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 Saint Marys

In Saint Marys in January humidity is 88%. With an average temperature of -2°C (30°F), this humidity feels like a biting chill that seeps into your bones, making it challenging to fully enjoy outdoor activities without bundling up in layers.

January Average Humidity in Saint Marys

This chart illustrates the average monthly humidity levels in Saint Marys, 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 Saint Marys is approximately 88%, 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 Saint Marys

In Saint Marys 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 Saint Marys, you can check the information here.

Maximum UV Index Levels in Saint Marys for January

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

Data source: Saint Marys 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 Saint Marys Compares to Other Months

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

This table compares monthly weather conditions in Saint Marys, 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 (30°F)	74 mm (2.9 inches)	88%	moderate
February Weather	0°C (32°F)	93 mm (3.7 inches)	87%	moderate
March Weather	5°C (42°F)	102 mm (4.0 inches)	87%	high
April Weather	10°C (51°F)	98 mm (3.9 inches)	87%	very high
May Weather	17°C (63°F)	130 mm (5.1 inches)	81%	very high
June Weather	22°C (72°F)	125 mm (4.9 inches)	82%	very high
July Weather	24°C (76°F)	109 mm (4.3 inches)	81%	very high
August Weather	23°C (73°F)	109 mm (4.3 inches)	78%	very high
September Weather	20°C (69°F)	73 mm (2.9 inches)	78%	very high
October Weather	14°C (57°F)	96 mm (3.8 inches)	82%	high
November Weather	5°C (42°F)	85 mm (3.4 inches)	89%	moderate
December Weather	2°C (35°F)	69 mm (2.7 inches)	86%	low