Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
May comes with an increase, with the average high-temperature moving from a mild 60.4°F (15.8°C) in April to an agreeable 72°F (22.2°C). During May in Merna, Illinois, the average low-temperature is recorded at a mild 55.4°F (13°C).Humidity
In May, the average relative humidity in Merna is 77%.Rainfall
May is the month with the most rainfall in Merna. Rain falls for 20.1 days and accumulates 4.57" (116mm) of precipitation.Snowfall
In Merna, snow does not fall in May through September.Daylight
In Merna, the average length of the day in May is 14h and 27min.On the first day of May, sunrise is at 5:53 am and sunset at 7:51 pm. On the last day of the month, sunrise is at 5:26 am and sunset at 8:19 pm CDT.
Sunshine
In May, the average sunshine in Merna, Illinois, is 8.7h.UV index
The average daily maximum UV index in May in Merna is 5. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for ordinary individuals.Note: In May, the average maximum UV index of 5 translates into the following recommendations:
Ensure safety - Imperative it is to shield skin and eyes from damage. Avoiding direct sun during mid-day hours can prevent harmful UV radiation exposure. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average May temperature in Merna?
What is the average humidity in May in Merna?
What is the wettest month in Merna?
How many days does it rain in May in Merna?
When it does not snow in Merna?
Does it snow in Merna in May?
What is the average length of the day in May in Merna?
When is the sunrise / sunset in May in Merna?
How long on average sun shines in May in Merna?
What is the UV index reading in May in Merna?
Average temperature in May
Merna, IL
- Average high temperature in May: 72°F
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (30.7°F).
- Average low temperature in May: 55.4°F
The month with the highest average low temperature is July (64.9°F).
The coldest month (with the lowest average low temperature) is January (18.9°F).
Average pressure in May
Merna, IL
- Average pressure in May: 29.96"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in May
Merna, IL
- Average wind speed in May: 9.3mph
The windiest month (with the highest average wind speed) is January (11.1mph).
The calmest month (with the lowest average wind speed) is August (6.6mph).
Average humidity in May
Merna, IL
- Average humidity in May: 77%
The month with the highest relative humidity is July (86%).
The month with the lowest relative humidity is October (71%).
Average rainfall in May
Merna, IL
- Average rainfall in May: 4.57"
The wettest month (with the highest rainfall) is May (4.57").
The driest month (with the least rainfall) is December (1.93").
Average rainfall days in May
Merna, IL
- Average rainfall days in May: 20.1 days
The month with the highest number of rainy days is May (20.1 days).
The month with the least rainy days is February (6.9 days).
Average snowfall in May
Merna, IL
- Average snowfall in May: 0"
The month with the highest snowfall is January (5.04").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in May
Merna, IL
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (12.8 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Merna, IL
- Average daylight in May: 14h and 3min
The month with the longest days is June (Average daylight: 15h and 0min).
The month with the shortest days is December (Average daylight: 9h and 18min).
- Average sunshine in May: 8h and 4min
The month with the most sunshine is June (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 42min).
Average sunshine days in May
Merna, IL
- Average sunshine days in May: 8.4 days
The month with the most sunshine days is November (17.4 days).
The month with the least sunshine days is May (8.4 days).
Average UV index in May
Merna, 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, February, October, November and December (UV index 2).
Average cloud cover in May
Merna, IL
- Average cloud cover in May: 42
The month with the most cloud cover is January (Cloud cover 60).
The months with the least cloud cover are August and September (Cloud cover 33).
Average visibility in May
Merna, IL
- Average visibility in May: 6mi
The months with the highest visibility are February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, July and August (5mi).
Merna, Illinois, USA
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