October Weather in Saint Charles, United States

Last updated: June 24, 2025

In October, the average temperature in Saint Charles, United States is a comfortable 17°C (64°F), with fluctuating conditions that can see lows of 4°C (39°F) and highs reaching up to 35°C (95°F). Expect 108 mm (4.2 in) of precipitation spread over about 9 days, contributing to an average humidity of 81%. Be prepared for a mix of pleasant warmth and occasional rain!

October Temperature in Saint Charles

In October in Saint Charles, the average temperature is 17°C (64°F). The maximum can reach 35°C (95°F) and the minimum can be as low as 4°C (39°F). This makes it an ideal destination for travelers seeking a pleasant climate with comfortable daytime temperatures and cooler evenings.

October Weather in Saint Charles: Daily Temperature Highs, Lows, and Averages

The chart illustrates October temperature patterns in Saint Charles, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Saint Charles, October typically has an average temperature of 17°C (64°F), with highs reaching up to 35°C (95°F) and lows dropping to around 4°C (39°F).

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

October Precipitation in Saint Charles

In Saint Charles in October, the precipitation amount is 108 mm (4.2 in) spread over 9 days.

October Precipitation Trends in Saint Charles

The chart displays monthly precipitation patterns in Saint Charles, with values for each month alongside October’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how October’s conditions compare to those of other months. In Saint Charles, October typically receives around 108 mm (4.2 inches) of precipitation spread over approximately 9 days.

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

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Millimeters (mm) Inches (in)

October Humidity in Saint Charles

In Saint Charles in October, humidity is 81%. With an average temperature of 17°C (64°F), this humidity feels like walking through a warm mist, enveloping you in a sticky embrace that can quickly lead to discomfort during long sightseeing excursions.

October Average Humidity in Saint Charles

This chart illustrates the average monthly humidity levels in Saint Charles, with October’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In October, average humidity in Saint Charles is approximately 81%, offering insight into how humid the weather typically is during this month.

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

October UV Index in Saint Charles

In Saint Charles in October, 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 Saint Charles.

Maximum UV Index Levels in Saint Charles for October

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

Data source: Saint Charles October 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 October Weather in Saint Charles Compares to Other Months

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

This table compares monthly weather conditions in Saint Charles, showing how October’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	4°C (39°F)	62 mm (2.4 inches)	84%	moderate
February Weather	6°C (42°F)	93 mm (3.7 inches)	83%	moderate
March Weather	9°C (48°F)	77 mm (3.0 inches)	83%	high
April Weather	14°C (58°F)	99 mm (3.9 inches)	81%	very high
May Weather	19°C (67°F)	118 mm (4.6 inches)	78%	very high
June Weather	24°C (76°F)	106 mm (4.2 inches)	79%	very high
July Weather	27°C (81°F)	122 mm (4.8 inches)	74%	very high
August Weather	26°C (79°F)	151 mm (5.9 inches)	72%	very high
September Weather	23°C (73°F)	91 mm (3.6 inches)	75%	very high
October Weather	17°C (64°F)	108 mm (4.2 inches)	81%	high
November Weather	9°C (49°F)	78 mm (3.1 inches)	85%	moderate
December Weather	6°C (43°F)	86 mm (3.4 inches)	84%	moderate