April Weather in Alton, United States

Last updated: June 24, 2025

In April, the average temperature in Alton, United States hovers around 7°C (44°F), with temperatures ranging from a brisk -5°C (24°F) to a pleasant 26°C (79°F). Expect 128 mm (5.0 in) of precipitation spread across 12 days, while humidity remains comfortably high at 80%.

April Temperature in Alton

In April in Alton, the average temperature is 7°C (44°F). Maximum temperatures can reach 26°C (79°F), while the minimum can drop as low as -5°C (24°F). Be sure to pack layers to accommodate the fluctuating temperatures during your travels!

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

The chart illustrates April 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, April typically has an average temperature of 7°C (44°F), with highs reaching up to 26°C (79°F) and lows dropping to around -5°C (24°F).

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

April Precipitation in Alton

In Alton in April, the precipitation amount is 128 mm (5.0 in) over the course of 12 days.

April Precipitation Trends in Alton

The chart displays monthly precipitation patterns in Alton, with values for each month alongside April’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how April’s conditions compare to those of other months. In Alton, April typically receives around 128 mm (5.0 inches) of precipitation spread over approximately 12 days.

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

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Millimeters (mm) Inches (in)

April Humidity in Alton

In Alton in April humidity is 80%. With an average temperature of 7°C (44°F), this humidity feels like a chilly dampness that clings to your skin, making it essential to dress in layers and be prepared for a slightly uncomfortable but invigorating travel experience.

April Average Humidity in Alton

This chart illustrates the average monthly humidity levels in Alton, with April’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In April, average humidity in Alton is approximately 80%, offering insight into how humid the weather typically is during this month.

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

April UV Index in Alton

In Alton in April, 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 Alton.

Maximum UV Index Levels in Alton for April

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

Data source: Alton April 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 April 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 April’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 April’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