Naperville
Illinois, USA
Long-term weather forecast
Long-term weather forecast

May weather forecast and climate
Naperville, IL

The scenic view of a covered bridge over a river along the famous Naperville Riverwalk in Naperville, Illinois, reflections in the below water
The scenic view of a covered bridge over a river along the famous Naperville Riverwalk in Naperville, Illinois, reflections in the below water
May, the last month of the spring, in Naperville, is an agreeable month, with average temperature varying between 51.8°F (11°C) and 69.1°F (20.6°C).

Temperature

In May, the average high-temperature increases, from a mild 56.8°F (13.8°C) in April, to an agreeable 69.1°F (20.6°C). In Naperville, the average low-temperature is 51.8°F (11°C).

Humidity

In Naperville, the average relative humidity in May is 76%.

Rainfall

The month with the most rainfall in Naperville is May when the rain falls for 14.8 days and typically aggregates up to 2.09" (53mm) of precipitation.

Snowfall

In Naperville snow does not fall through September.

Daylight

In Naperville, the average length of the day is 14.6h.

Sunshine

In Naperville, the average sunshine in May is 8.6h.

UV index

In Naperville, the average daily maximum UV index in May is 5. A UV Index of 3 to 5 symbolizes a moderate health risk from the exposure to the Sun's UV rays for the average person.
Note: The daily maximum UV index of 5 interpret into the following advice:
Take precautions. Light skin individuals may get burned in less than 30 minutes. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. On bright days sunglasses that block both UVA and UVB rays should be worn. A hat with a wide brim is extremely helpful, as it can prevent roughly 50% of UV radiation from reaching the eyes. Caution! The reflection of snow can nearly double the intensity of the Sun's UV radiation.

What is the temperature in May in Naperville?

The average high-temperature, in May, in Naperville, is 69.1°F (20.6°C), while the average low-temperature is 51.8°F (11°C).

What is the average humidity in May in Naperville?

The average relative humidity in May in Naperville is 76%.

How much does it rain in Naperville in May?

In May, the rain falls for 14.8 days. Throughout May, 2.09" (53mm) of precipitation is accumulated.

What is the wettest month in Naperville?

May is the month with the most rainfall. Rain falls for 14.8 days and accumulates 2.09" (53mm) of precipitation.

Does it snow in Naperville in May?

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

When it does not snow in Naperville?

In Naperville snow does not fall in May through September.

What is the average length of the day in May in Naperville?

The average length of the day in May is 14.6h.

How many hours of sunshine does Naperville have in May?

In Naperville, the average sunshine in May is 8.6h.

How high is the UV index in May in Naperville?

In Naperville, the average daily maximum UV index in May is 5. A UV Index estimate of 3 to 5 represents a medium health risk from unsafe exposure to the Sun's UV rays.
Average temperature in May - Naperville, IL
  • Average high temperature in May: 20.6°C

The warmest month (with the highest average high temperature) is July (27.6°C).
The month with the lowest average high temperature is January (-2°C).

  • Average low temperature in May: 11°C

The month with the highest average low temperature is July (18.4°C).
The coldest month (with the lowest average low temperature) is January (-8.3°C).

Average humidity in May - Naperville, IL
  • Average humidity in May: 76%

Months with the highest relative humidity are January and February (83%).
The month with the lowest relative humidity is October (73%).

Average rainfall in May - Naperville, IL
  • Average rainfall in May: 53mm

The wettest month (with the highest rainfall) is May (53mm).
The driest month (with the lowest rainfall) is December (18mm).

Average rainfall days in May - Naperville, IL
  • Average rainfall days in May: 14.8 days

The month with the highest number of rainy days is July (17.3 days).
The month with the lowest number of rainy days is February (4.4 days).

Average snowfall in May - Naperville, IL
  • Average snowfall in May: 0mm

The month with the highest snowfall is January (47mm).
Months with the lowest snowfall are May, June, July, August and September (0mm).

Average snowfall days in May - Naperville, IL
  • Average snowfall days in May: 0.1 days

The month with the highest number of snowfall days is January (11.1 days).
Months with the lowest number of snowfall days are June, July, August and September (0 days).

Average daylight in May / Average sunshine in May - Naperville, IL
  • Average daylight in May: 14.6h

The month with the longest days is June (Average daylight: 15.2h).
The month with shortest days is December (Average daylight: 9.2h).

  • Average sunshine in May: 8.6h

Months with most sunshine are July and August (Average sunshine: 10h).
The month with least sunshine is January (Average sunshine: 3.8h).

Average UV index in May - Naperville, IL
  • Average UV index in May: 5

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