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 brings an increase in the average high-temperature, progressing from a comfortable 66.4°F (19.1°C) in April to a moderately hot 75.6°F (24.2°C). The nighttime temperature in Johnston City dips to a moderate 58.1°F (14.5°C) on average during May.Humidity
With an average relative humidity of 79%, May is the most humid month.Rainfall
In Johnston City, during May, the rain falls for 18.5 days and regularly aggregates up to 4.25" (108mm) of precipitation. Throughout the year, in Johnston City, Illinois, there are 167.2 rainfall days, and 37.68" (957mm) of precipitation is accumulated.Snowfall
May through September are months without snowfall.Daylight
In May, the average length of the day in Johnston City is 14h and 14min.On the first day of May, sunrise is at 5:58 am and sunset at 7:46 pm. On the last day of the month, sunrise is at 5:35 am and sunset at 8:11 pm CDT.
Sunshine
In May, the average sunshine in Johnston City, Illinois, is 9.2h.UV index
May through August, with an average maximum UV index of 6, are months with the highest UV index in Johnston City, Illinois. A UV Index estimate of 6 to 7 represents a high threat to health from unprotected exposure to Sun's UV rays for the ordinary person.Note: In May, a daily maximum UV index of 6 leads to the following instructions:
Avoid excessive sunlight. Those with lighter skin may experience burning in less than 20 minutes. Remember that UV radiation from the Sun is strongest between 10 a.m. and 4 p.m. Make an effort to limit direct sun exposure during this time. For effective sun eye protection, rely on sunglasses certified for UVA and UVB resistance.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average May temperature in Johnston City?
What is the most humid month in Johnston City?
What is the average humidity in May in Johnston City?
How many days does it rain in May in Johnston City?
When it does not snow in Johnston City?
Does it snow in Johnston City in May?
What is the average length of the day in May in Johnston City?
When are sunrise and sunset in May in Johnston City?
How long on average sun shines in May in Johnston City?
When is the highest UV index in Johnston City?
What is the UV index reading in May in Johnston City?
Average temperature in May
Johnston City, IL
- Average high temperature in May: 75.6°F
The warmest month (with the highest average high temperature) is July (87.3°F).
The month with the lowest average high temperature is January (39°F).
- Average low temperature in May: 58.1°F
The month with the highest average low temperature is July (68.5°F).
The coldest month (with the lowest average low temperature) is January (26.1°F).
Average pressure in May
Johnston City, IL
- Average pressure in May: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.94"Hg).
Average wind speed in May
Johnston City, IL
- Average wind speed in May: 7.9mph
The windiest months (with the highest average wind speed) are January and February (9.6mph).
The calmest months (with the lowest average wind speed) are July and August (5.8mph).
Average humidity in May
Johnston City, IL
- Average humidity in May: 79%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in May
Johnston City, IL
- Average rainfall in May: 4.25"
The wettest month (with the highest rainfall) is April (4.92").
The driest month (with the least rainfall) is September (1.97").
Average rainfall days in May
Johnston City, IL
- Average rainfall days in May: 18.5 days
The month with the highest number of rainy days is May (18.5 days).
The month with the least rainy days is January (9.7 days).
Average snowfall in May
Johnston City, IL
- Average snowfall in May: 0"
The month with the highest snowfall is February (1.93").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in May
Johnston City, IL
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (6.1 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
Johnston City, IL
- Average daylight in May: 14h and 1min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in May: 9h and 1min
The months with the most sunshine are June and July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 36min).
Average sunshine days in May
Johnston City, IL
- Average sunshine days in May: 10 days
The month with the most sunshine days is October (17.6 days).
The month with the least sunshine days is June (9.9 days).
Average UV index in May
Johnston City, 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 and December (UV index 2).
Average cloud cover in May
Johnston City, IL
- Average cloud cover in May: 38
The month with the most cloud cover is February (Cloud cover 51).
The month with the least cloud cover is June (Cloud cover 28).
Average visibility in May
Johnston City, 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).
Johnston City, Illinois, USA
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