January Weather in Dayton, United States

Last updated: June 24, 2025

In January, the average temperature in Dayton, United States hovers around -2°C (29°F). While you might experience a chilling minimum of -27°C (-17°F), the days can also bring a surprising maximum of 18°C (65°F). Expect 76 mm (3.0 in) of precipitation over 9 days during this period, with an average humidity of 85% adding to the atmosphere.

January Temperature in Dayton

In January in Dayton, the average temperature is -2°C (29°F). Maximum temperatures can reach 18°C (65°F), while the minimum can drop as low as -27°C (-17°F). Visitors should be prepared for a wide range of weather conditions when traveling during this time.

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

The chart illustrates January temperature patterns in Dayton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Dayton, January typically has an average temperature of -2°C (29°F), with highs reaching up to 18°C (65°F) and lows dropping to around -27°C (-17°F).

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

January Precipitation in Dayton

In Dayton in January, the precipitation amount is 76 mm (3.0 in) spread over a period of 9 days.

January Precipitation Trends in Dayton

The chart displays monthly precipitation patterns in Dayton, 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 Dayton, January typically receives around 76 mm (3.0 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 Dayton

In Dayton in January, humidity is 85%. With an average temperature of -2°C (29°F), this humidity feels like a chilling, damp blanket that clings to your skin, making travel uncomfortable and often prompting an urgent search for warmth and shelter.

January Average Humidity in Dayton

This chart illustrates the average monthly humidity levels in Dayton, 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 Dayton is approximately 85%, 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 Dayton

In Dayton 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 Dayton, you can check the information here.

Maximum UV Index Levels in Dayton for January

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

Data source: Dayton 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 Dayton Compares to Other Months

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

This table compares monthly weather conditions in Dayton, 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)	76 mm (3.0 inches)	85%	moderate
February Weather	0°C (32°F)	79 mm (3.1 inches)	85%	moderate
March Weather	6°C (42°F)	107 mm (4.2 inches)	86%	high
April Weather	11°C (52°F)	92 mm (3.6 inches)	87%	very high
May Weather	18°C (64°F)	143 mm (5.6 inches)	81%	very high
June Weather	23°C (74°F)	95 mm (3.7 inches)	82%	very high
July Weather	25°C (77°F)	92 mm (3.6 inches)	81%	very high
August Weather	23°C (74°F)	86 mm (3.4 inches)	79%	very high
September Weather	21°C (70°F)	63 mm (2.5 inches)	78%	very high
October Weather	14°C (58°F)	105 mm (4.1 inches)	81%	high
November Weather	5°C (42°F)	76 mm (3.0 inches)	89%	moderate
December Weather	2°C (36°F)	64 mm (2.5 inches)	86%	low