May weather forecastSaint Charles, IL

May

Weather in May

May, the last month of the spring in Saint Charles, is an agreeable month, with an average temperature ranging between max 68.2°F (20.1°C) and min 51.4°F (10.8°C).

Temperature

With the arrival of May, the average high-temperature transitions from a moderate 56.1°F (13.4°C) in April to an agreeable 68.2°F (20.1°C). In May, the temperature drops to an average of 51.4°F (10.8°C) at night.

Humidity

In May, the average relative humidity in Saint Charles is 78%.

Rainfall

The month with the most rainfall in Saint Charles is May, when the rain falls for 12.4 days and typically aggregates up to 1.26" (32mm) of precipitation.

Snowfall

In Saint Charles, snow does not fall in May through September.

Daylight

In Saint Charles, the average length of the day in May is 14h and 35min.
On the first day of the month, sunrise is at 5:48 am and sunset at 7:52 pm. On the last day of May, sunrise is at 5:20 am and sunset at 8:21 pm CDT.

Sunshine

In May, the average sunshine in Saint Charles is 8.5h.

UV index

In May, the average daily maximum UV index in Saint Charles is 5. A UV Index of 3 to 5 symbolizes a medium vulnerability from exposure to the Sun's UV radiation for average individuals.
Note: The maximum UV index of 5 during May leads to these instructions:
Be mindful. Those with pale skin might receive burns in fewer than 30 minutes. Considering the Sun's intensity during midday, it's wise to minimize direct exposure. Safeguard your eyes, ears, and face from sun rays with the aid of a wide-brim hat. Keep in mind! Snow's reflective quality can nearly double the intensity of the Sun's UV radiation.
Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

During May, Saint Charles experiences an average high-temperature of 68.2°F (20.1°C) and a low-temperature of 51.4°F (10.8°C).

In May, the average relative humidity in Saint Charles, Illinois, is 78%.

May is the month with the most rainfall in Saint Charles. Rain falls for 12.4 days and accumulates 1.26" (32mm) of precipitation.

In Saint Charles, during May, the rain falls for 12.4 days and regularly aggregates up to 1.26" (32mm) of precipitation.

In Saint Charles, Illinois, snow does not fall in May through September.

In May, in Saint Charles, it doesn't snow. April is the latest month when it typically snows.

In Saint Charles, the average day length in May is 14h and 35min.

On the first day of May in Saint Charles, Illinois, sunrise is at 5:48 am and sunset at 7:52 pm. On the last day of the month, sunrise is at 5:20 am and sunset at 8:21 pm CDT.

In Saint Charles, the average sunshine duration in May is 8.5h.

The average daily maximum UV index in May in Saint Charles is 5. A UV Index estimate of 3 to 5 represents a moderate health threat from exposure to Sun's UV rays.
Average high temperature
Average low temperature
Average pressure
Average wind speed
Average max. wind speed
Average wind speed gusts
Average humidity
Average rainfall
Average rainfall days
Average snowfall
Average snowfall days
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in May
Saint Charles, IL

  • Average high temperature in May: 68.2°F

The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (27.9°F).

  • Average low temperature in May: 51.4°F

The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is January (16.2°F).

Average pressure in May
Saint Charles, IL

  • Average pressure in May: 29.96"Hg

The month with the highest atmospheric pressure is January (30.11"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

Average wind speed in May
Saint Charles, IL

  • Average wind speed in May: 8.2mph

The windiest month (with the highest average wind speed) is January (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.1mph).

Average humidity in May
Saint Charles, IL

  • Average humidity in May: 78%

The months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (74%).

Average rainfall in May
Saint Charles, IL

  • Average rainfall in May: 1.26"

The wettest month (with the highest rainfall) is May (1.26").
The driest months (with the least rainfall) are November and December (0.39").

Average rainfall days in May
Saint Charles, IL

  • Average rainfall days in May: 12.4 days

The month with the highest number of rainy days is May (12.4 days).
The month with the least rainy days is January (3.4 days).

Average snowfall in May
Saint Charles, IL

  • Average snowfall in May: 0"

The month with the highest snowfall is January (1.14").
The months with the least snowfall are May, June, July, August and September (0").

Average snowfall days in May
Saint Charles, IL

  • Average snowfall days in May: 0.1 days

The month with the highest number of snowfall days is January (7.6 days).
The months with the least snowfall days are June, July, August and September (0 days).

Average daylight in May /
Average sunshine in May
Saint Charles, IL

  • Average daylight in May: 14h and 36min

The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).

  • Average sunshine in May: 8h and 30min

The month with the most sunshine is July (Average sunshine: 9h and 54min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).

Average sunshine days in May
Saint Charles, IL

  • Average sunshine days in May: 14.9 days

The month with the most sunshine days is December (22.4 days).
The month with the least sunshine days is June (13.3 days).

Average UV index in May
Saint Charles, IL

  • Average UV index in May: 5

The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January and December (UV index 1).

Average cloud cover in May
Saint Charles, IL

  • Average cloud cover in May: 43

The month with the most cloud cover is January (Cloud cover 62).
The month with the least cloud cover is September (Cloud cover 32).

Average visibility in May
Saint Charles, IL

  • Average visibility in May: 6mi

The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).