August Weather in Alton, United States

Last updated: June 24, 2025

In August, the average temperature in Alton, United States is a pleasant 21°C (71°F), with the mercury ranging from a minimum of 10°C (50°F) to a maximum of 35°C (95°F). Expect an average precipitation of 74 mm (2.9 in) spread over 9 days, accompanied by a moderate average humidity of 66%. Perfect weather for exploring!

August Temperature in Alton

In August in Alton, the average temperature is 21°C (71°F). Maximums can reach 35°C (95°F), and minimums can be as low as 10°C (50°F). It's a great time to visit for those who enjoy warm weather with occasional cooler evenings.

August Weather in Alton: Daily Temperature Highs, Lows, and Averages

The chart illustrates August temperature patterns in Alton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Alton, August typically has an average temperature of 21°C (71°F), with highs reaching up to 35°C (95°F) and lows dropping to around 10°C (50°F).

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

August Precipitation in Alton

In Alton in August, the precipitation amount is 74 mm (2.9 in), which occurs over a span of 9 days.

August Precipitation Trends in Alton

The chart displays monthly precipitation patterns in Alton, with values for each month alongside August’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how August’s conditions compare to those of other months. In Alton, August typically receives around 74 mm (2.9 inches) of precipitation spread over approximately 9 days.

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

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Millimeters (mm) Inches (in)

August Humidity in Alton

In Alton in August, humidity is 66%. With an average temperature of 21°C (71°F), this humidity feels like a warm, sticky embrace that can make outdoor activities a bit taxing but also lends a vibrant energy to the atmosphere, ideal for those who appreciate a tropical ambiance while exploring.

August Average Humidity in Alton

This chart illustrates the average monthly humidity levels in Alton, with August’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In August, average humidity in Alton is approximately 66%, offering insight into how humid the weather typically is during this month.

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

August UV Index in Alton

In Alton in August, the maximum UV index is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, you can check the Hourly UV Index in Alton.

Maximum UV Index Levels in Alton for August

The chart shows the monthly maximum UV Index (UVI) for Alton in August, 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 August, the maximum UV index in Alton typically reaches 9, which falls under the very high exposure category.

Data source: Alton August 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 August Weather in Alton Compares to Other Months

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

This table compares monthly weather conditions in Alton, showing how August’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-5°C (24°F)	75 mm (2.9 inches)	86%	moderate
February Weather	-3°C (27°F)	84 mm (3.3 inches)	84%	moderate
March Weather	0°C (33°F)	77 mm (3.0 inches)	82%	moderate
April Weather	7°C (44°F)	128 mm (5.0 inches)	80%	very high
May Weather	13°C (56°F)	74 mm (2.9 inches)	72%	very high
June Weather	19°C (66°F)	87 mm (3.4 inches)	72%	very high
July Weather	22°C (72°F)	134 mm (5.3 inches)	67%	very high
August Weather	21°C (71°F)	74 mm (2.9 inches)	66%	very high
September Weather	18°C (64°F)	66 mm (2.6 inches)	71%	high
October Weather	11°C (52°F)	119 mm (4.7 inches)	78%	moderate
November Weather	3°C (39°F)	110 mm (4.3 inches)	84%	moderate
December Weather	-2°C (29°F)	119 mm (4.7 inches)	81%	low