September Weather in Libby, United States

Last updated: June 24, 2025

In September, the average temperature in Libby, United States hovers around 13°C (55°F). However, be prepared for a wide range; minimum temperatures can plummet to -3°C (27°F), while highs may reach up to 31°C (88°F). With an average precipitation of 44 mm (1.7 in) spread over 7 days, and 71% average humidity, it's wise to be ready for both sun and showers!

September Temperature in Libby

In September in Libby, the average temperature is 13°C (55°F). The maximum can reach 31°C (88°F) and the minimum can be as low as -3°C (27°F). Be prepared for a wide range of temperatures, making it essential to pack layers for your travels.

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

The chart illustrates September temperature patterns in Libby, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Libby, September typically has an average temperature of 13°C (55°F), with highs reaching up to 31°C (88°F) and lows dropping to around -3°C (27°F).

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

September Precipitation in Libby

In Libby in September, the precipitation amount is 44 mm (1.7 in) spread over a duration of 7 days.

September Precipitation Trends in Libby

The chart displays monthly precipitation patterns in Libby, 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 Libby, September typically receives around 44 mm (1.7 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 Libby

In Libby in September humidity is 71%. With an average temperature of 13°C (55°F), this humidity feels like a damp embrace, making travel a bit challenging as the moisture clings to your skin and the air feels thick, creating a sense of heaviness that can sap your energy while exploring.

September Average Humidity in Libby

This chart illustrates the average monthly humidity levels in Libby, 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 Libby is approximately 71%, 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 Libby

In Libby 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 Libby.

Maximum UV Index Levels in Libby for September

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

Data source: Libby 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 Libby Compares to Other Months

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

This table compares monthly weather conditions in Libby, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-5°C (23°F)	76 mm (3.0 inches)	95%	low
February Weather	-7°C (20°F)	95 mm (3.8 inches)	93%	moderate
March Weather	0°C (32°F)	66 mm (2.6 inches)	91%	high
April Weather	4°C (39°F)	74 mm (2.9 inches)	88%	high
May Weather	10°C (51°F)	66 mm (2.6 inches)	83%	very high
June Weather	15°C (59°F)	45 mm (1.8 inches)	80%	very high
July Weather	20°C (68°F)	16 mm (0.6 inches)	82%	very high
August Weather	19°C (66°F)	25 mm (1.0 inches)	71%	very high
September Weather	13°C (55°F)	44 mm (1.7 inches)	71%	high
October Weather	5°C (41°F)	87 mm (3.4 inches)	85%	moderate
November Weather	0°C (32°F)	92 mm (3.6 inches)	90%	moderate
December Weather	-3°C (26°F)	102 mm (4.0 inches)	96%	low