September Weather in Merrill, United States

Last updated: June 24, 2025

In September, the average temperature in Merrill, United States hovers around 15°C (60°F), with a minimum dipping to 0°C (31°F) and a maximum reaching 31°C (89°F). Expect around 85 mm (3.3 in) of precipitation over about 11 days, while the average humidity remains comfortably high at 78%.

September Temperature in Merrill

In September, in Merrill, the average temperature is 15°C (60°F), with maximums reaching 31°C (89°F) and minimums dropping as low as 0°C (31°F). This weather makes it essential for travelers to pack layers to stay comfortable throughout the day.

September Weather in Merrill: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Merrill, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Merrill, September typically has an average temperature of 15°C (60°F), with highs reaching up to 31°C (89°F) and lows dropping to around 0°C (31°F).

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

September Precipitation in Merrill

In Merrill in September, the total precipitation amount is 85 mm (3.3 in) over a span of 11 days.

September Precipitation Trends in Merrill

The chart displays monthly precipitation patterns in Merrill, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Merrill, September typically receives around 85 mm (3.3 inches) of precipitation spread over approximately 11 days.

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

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Millimeters (mm) Inches (in)

September Humidity in Merrill

In Merrill in September, humidity is 78%. With an average temperature of 15°C (60°F), this humidity feels like a warm, damp embrace that can make outdoor activities a bit uncomfortable, highlighting the importance of staying hydrated and taking breaks in the shade while exploring.

September Average Humidity in Merrill

This chart illustrates the average monthly humidity levels in Merrill, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Merrill is approximately 78%, offering insight into how humid the weather typically is during this month.

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

September UV Index in Merrill

In Merrill in September, the maximum UV index is 7, which corresponds to the high Exposure Category. This means that the time to burn is approximately 25 minutes. For more detailed information, you can check the Hourly UV Index in Merrill.

Maximum UV Index Levels in Merrill for September

The chart shows the monthly maximum UV Index (UVI) for Merrill in September, 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 September, the maximum UV index in Merrill typically reaches 7, which falls under the high exposure category.

Data source: Merrill September 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 September Weather in Merrill Compares to Other Months

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

This table compares monthly weather conditions in Merrill, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-9°C (16°F)	32 mm (1.3 inches)	89%	low
February Weather	-9°C (16°F)	51 mm (2.0 inches)	90%	moderate
March Weather	-1°C (30°F)	49 mm (1.9 inches)	87%	moderate
April Weather	5°C (41°F)	98 mm (3.8 inches)	84%	high
May Weather	13°C (56°F)	100 mm (3.9 inches)	77%	very high
June Weather	19°C (66°F)	99 mm (3.9 inches)	75%	very high
July Weather	21°C (70°F)	119 mm (4.7 inches)	74%	very high
August Weather	19°C (67°F)	117 mm (4.6 inches)	73%	very high
September Weather	15°C (60°F)	85 mm (3.3 inches)	78%	high
October Weather	8°C (46°F)	116 mm (4.6 inches)	84%	moderate
November Weather	-1°C (31°F)	49 mm (1.9 inches)	89%	moderate
December Weather	-6°C (22°F)	53 mm (2.1 inches)	87%	low