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
The onset of May marks an increase in the average high-temperature, moving from a mild 59°F (15°C) in April to a pleasant 70.3°F (21.3°C). Throughout May, the temperature tends to fall to a consistent average low of 53.4°F (11.9°C).Humidity
In May, the average relative humidity is 77%.Rainfall
May is the month with the most rainfall. Rain falls for 13.4 days and accumulates 1.61" (41mm) of precipitation.Snowfall
In Port Byron, snow does not fall in May through August.Daylight
In Port Byron, the average length of the day in May is 14h and 33min.On the first day of the month, sunrise is at 5:56 am and sunset at 7:59 pm. On the last day of May, sunrise is at 5:29 am and sunset at 8:28 pm CDT.
Sunshine
In Port Byron, the average sunshine in May is 8.6h.UV index
In May, the average daily maximum UV index is 5. A UV Index value of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the average person.Note: A typical high UV index of 5 in May suggests the following recommendations:
Put precautions into practice - Ensuring skin and eye safety is a necessity. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in May?
What is the average humidity in May?
What is the wettest month?
How many days does it rain in May?
When it does not snow?
Does it snow in May?
What is the average length of the day in May?
What time are sunrise and sunset in May?
How many hours of sunshine does Port Byron have in May?
How high is the UV index in May?
Average temperature in May
Port Byron, IL
- Average high temperature in May: 70.3°F
The warmest month (with the highest average high temperature) is July (81.7°F).
The month with the lowest average high temperature is January (28.2°F).
- Average low temperature in May: 53.4°F
The month with the highest average low temperature is July (64.8°F).
The coldest month (with the lowest average low temperature) is January (15.4°F).
Average pressure in May
Port Byron, IL
- Average pressure in May: 29.95"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).
Average wind speed in May
Port Byron, IL
- Average wind speed in May: 9mph
The windiest month (with the highest average wind speed) is April (10.6mph).
The calmest month (with the lowest average wind speed) is August (6.7mph).
Average humidity in May
Port Byron, IL
- Average humidity in May: 77%
The months with the highest relative humidity are January and July (83%).
The month with the lowest relative humidity is October (71%).
Average rainfall in May
Port Byron, IL
- Average rainfall in May: 1.61"
The wettest month (with the highest rainfall) is May (1.61").
The driest month (with the least rainfall) is December (0.35").
Average rainfall days in May
Port Byron, IL
- Average rainfall days in May: 13.4 days
The month with the highest number of rainy days is May (13.4 days).
The month with the least rainy days is January (3.2 days).
Average snowfall in May
Port Byron, IL
- Average snowfall in May: 0"
The month with the highest snowfall is January (1.26").
The months with the least snowfall are May, June, July and August (0").
Average snowfall days in May
Port Byron, IL
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (7.2 days).
The months with the least snowfall days are May, June, July and August (0 days).
Average daylight in May /
Average sunshine in May
Port Byron, IL
- Average daylight in May: 14h and 3min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in May: 8h and 4min
The month with the most sunshine is July (Average sunshine: 10h and 6min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in May
Port Byron, IL
- Average sunshine days in May: 14.6 days
The month with the most sunshine days is December (22.4 days).
The month with the least sunshine days is June (14.4 days).
Average UV index in May
Port Byron, IL
- Average UV index in May: 5
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is January (UV index 1).
Average cloud cover in May
Port Byron, IL
- Average cloud cover in May: 43
The month with the most cloud cover is January (Cloud cover 58).
The month with the least cloud cover is August (Cloud cover 30).
Average visibility in May
Port Byron, 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).
Port Byron, Illinois, USA
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