September Weather in North Spearfish, United States

Last updated: June 24, 2025

In September, the average temperature in North Spearfish, United States hovers around 15°C (60°F). Temperatures can vary significantly, with minimums dipping to -3°C (27°F) and maximums soaring to 37°C (99°F). During this period, expect about 46 mm (1.8 in) of precipitation spread across 7 days, contributing to an average humidity of 77%.

September Temperature in North Spearfish

In September in North Spearfish, the average temperature is 15°C (60°F). Maximums can reach 37°C (99°F), while minimums can drop as low as -3°C (27°F). This means travelers should be prepared for a wide range of temperatures and pack accordingly.

September Weather in North Spearfish: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in North Spearfish, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In North Spearfish, September typically has an average temperature of 15°C (60°F), with highs reaching up to 37°C (99°F) and lows dropping to around -3°C (27°F).

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

September Precipitation in North Spearfish

In North Spearfish in September, the precipitation amount is 46 mm (1.8 in) over the course of 7 days.

September Precipitation Trends in North Spearfish

The chart displays monthly precipitation patterns in North Spearfish, 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 North Spearfish, September typically receives around 46 mm (1.8 inches) of precipitation spread over approximately 7 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

September Humidity in North Spearfish

In North Spearfish in September, humidity is 77%. With an average temperature of 15°C (60°F), this humidity feels like you're wading through a warm, heavy blanket, making travel feel more exhausting and sticky than usual.

September Average Humidity in North Spearfish

This chart illustrates the average monthly humidity levels in North Spearfish, 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 North Spearfish is approximately 77%, 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 North Spearfish

In North Spearfish in September, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in North Spearfish.

Maximum UV Index Levels in North Spearfish for September

The chart shows the monthly maximum UV Index (UVI) for North Spearfish 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 North Spearfish typically reaches 8, which falls under the very high exposure category.

Data source: North Spearfish 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 North Spearfish Compares to Other Months

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

This table compares monthly weather conditions in North Spearfish, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-4°C (26°F)	23 mm (0.9 inches)	77%	moderate
February Weather	-6°C (21°F)	35 mm (1.4 inches)	80%	moderate
March Weather	1°C (35°F)	40 mm (1.6 inches)	70%	high
April Weather	4°C (40°F)	77 mm (3.0 inches)	70%	very high
May Weather	11°C (51°F)	100 mm (3.9 inches)	76%	very high
June Weather	18°C (65°F)	66 mm (2.6 inches)	84%	extreme
July Weather	22°C (71°F)	93 mm (3.7 inches)	85%	extreme
August Weather	20°C (68°F)	60 mm (2.4 inches)	84%	very high
September Weather	15°C (60°F)	46 mm (1.8 inches)	77%	very high
October Weather	6°C (43°F)	65 mm (2.6 inches)	73%	moderate
November Weather	2°C (36°F)	23 mm (0.9 inches)	74%	moderate
December Weather	-2°C (29°F)	32 mm (1.3 inches)	79%	low