May weather forecast
Collinsville, IL

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Weather in May

The last month of the spring, May, is a warm month in Collinsville, Illinois, with an average temperature ranging between max 74.5°F (23.6°C) and min 57.6°F (14.2°C).

Temperature

The start of May brings a rise in the average high-temperature, moving from an enjoyable 64.9°F (18.3°C) in April to a warm 74.5°F (23.6°C). May nights are marked by an average temperature drop to a mild 57.6°F (14.2°C).

Humidity

May, July and August, with an average relative humidity of 79%, are the most humid months.

Rainfall

The month with the most rainfall is May, when the rain falls for 17.1 days and typically aggregates up to 4.17" (106mm) of precipitation.

Snowfall

April through August and October are months without snowfall.

Daylight

In May, the average length of the day is 14h and 18min.
On the first day of the month, sunrise is at 6:01 am and sunset at 7:52 pm. On the last day of May, sunrise is at 5:37 am and sunset at 8:18 pm CDT.

Sunshine

In May, the average sunshine is 9.4h.

UV index

The months with the highest UV index are May through August, with an average maximum UV index of 6. A UV Index of 6 to 7 symbolizes a high health hazard from unsafe exposure to UV radiation for the average person.
Note: A maximum high daily UV index of 6 during May translates into the following directions:
Stick with precautions and abide by sun safety procedures. Evading sunburn is essential. Avoid direct Sun exposure and stay in the shade between 10 a.m. and 4 p.m., a time when UV radiation is most intense, noting that not all shade structures offer full protection. Shield yourself from the harmful effects of UV radiation with sun-protective attire, a hat, and quality sunglasses.
Updated: Jun 16, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What is the temperature in May in Collinsville?

In Collinsville, 74.5°F (23.6°C) is the average high-temperature and 57.6°F (14.2°C) is the average low-temperature during May.

What is the most humid month?

The months with the highest humidity are May, July and August, with an average relative humidity of 79%.

What is the average humidity in May?

In Collinsville, the average relative humidity in May is 79%.

What is the rainiest month in Collinsville?

May is the month with the most rainfall in Collinsville. Rain falls for 17.1 days and accumulates 4.17" (106mm) of precipitation.

How much does it rain in May?

In Collinsville, Illinois, during May, the rain falls for 17.1 days and regularly aggregates up to 4.17" (106mm) of precipitation.

When it does not snow?

In Collinsville, snow does not fall in April through August and October.

What is the average length of the day in May?

In Collinsville, the average day length in May is 14h and 18min.

What time are sunrise and sunset in May?

On the first day of May in Collinsville, sunrise is at 6:01 am and sunset at 7:52 pm. On the last day of the month, sunrise is at 5:37 am and sunset at 8:18 pm CDT.

How many hours of sunshine does Collinsville have in May?

In May, the average sunshine duration is 9.4h.

When is the highest UV index?

May through August, with an average maximum UV index of 6, are months with the highest UV index.

What is the UV index intensity in May?

The average daily maximum UV index in May is 6. A UV Index reading of 6 to 7 represents a high hazard to health from unprotected exposure to UV radiation.
Average humidity
Average rainfall days
Average snowfall
Average snowfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in May
Collinsville, IL

Average temperature in May - Collinsville, IL
  • Average high temperature in May: 74.5°F

The warmest month (with the highest average high temperature) is July (85.6°F).
The month with the lowest average high temperature is January (37.4°F).

  • Average low temperature in May: 57.6°F

The month with the highest average low temperature is July (68.2°F).
The coldest month (with the lowest average low temperature) is January (24.3°F).

Average pressure in May
Collinsville, IL

Average pressure in May - Collinsville, IL
  • Average pressure in May: 29.96"Hg

The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).

Average wind speed in May
Collinsville, IL

Average wind speed in May - Collinsville, IL
  • Average wind speed in May: 7.5mph

The windiest month (with the highest average wind speed) is January (9.5mph).
The calmest month (with the lowest average wind speed) is July (5.6mph).

Average humidity in May
Collinsville, IL

Average humidity in May - Collinsville, IL
  • Average humidity in May: 79%

The months with the highest relative humidity are May, July and August (79%).
The month with the lowest relative humidity is October (71%).

Average rainfall in May
Collinsville, IL

Average rainfall in May - Collinsville, IL
  • Average rainfall in May: 4.17"

The wettest month (with the highest rainfall) is May (4.17").
The driest month (with the least rainfall) is February (1.77").

Average rainfall days in May
Collinsville, IL

Average rainfall days in May - Collinsville, IL
  • Average rainfall days in May: 17.1 days

The month with the highest number of rainy days is May (17.1 days).
The month with the least rainy days is January (7.8 days).

Average snowfall in May
Collinsville, IL

Average snowfall in May - Collinsville, IL
  • Average snowfall in May: 0"

The month with the highest snowfall is January (2.13").
The months with the least snowfall are April, May, June, July, August and October (0").

Average snowfall days in May
Collinsville, IL

Average snowfall days in May - Collinsville, IL
  • Average snowfall days in May: 0 days

The month with the highest number of snowfall days is January (7 days).
The months with the least snowfall days are May, June, July and August (0 days).

Average daylight in May /
Average sunshine in May
Collinsville, IL

Average daylight in May / Average sunshine in May - Collinsville, IL
  • Average daylight in May: 14h and 2min

The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).

  • Average sunshine in May: 9h and 2min

The month with the most sunshine is June (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 30min).

Average sunshine days in May
Collinsville, IL

Average sunshine days in May - Collinsville, IL
  • Average sunshine days in May: 11.6 days

The month with the most sunshine days is December (18.6 days).
The month with the least sunshine days is May (11.6 days).

Average UV index in May
Collinsville, IL

Average UV index in May - Collinsville, IL
  • Average UV index in May: 6

The months with the highest UV index are May, June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).

Average cloud cover in May
Collinsville, IL

Average cloud cover in May - Collinsville, IL
  • Average cloud cover in May: 38

The month with the most cloud cover is January (Cloud cover 51).
The months with the least cloud cover are June and August (Cloud cover 28).

Average visibility in May
Collinsville, IL

Average visibility in May - Collinsville, IL
  • Average visibility in May: 6mi

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

Collinsville, Illinois, USA

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