July weather forecastJohnston, SC
July
Weather in July
July, the same as June, in Johnston, South Carolina, is a hot summer month, with temperature in the range of an average low of 72.5°F (22.5°C) and an average high of 91.4°F (33°C).Temperature
July is the month when Johnston experiences its warmest temperatures, averaging a high of 91.4°F (33°C) and a low of 72.5°F (22.5°C).Heat index
In July, the heat index is calculated to be an extremely hot 109.4°F (43°C). Remain alert: Heat exhaustion and heat cramps are predicted. Extended effort can lead to heatstroke.The standards for the heat index are set for locations in shade and under light breezes. The heat index may scale up by 15 Fahrenheit (8 Celsius) degrees with direct sun exposure.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', determines the feeling of heat when you account for the relative humidity. The influence of weather is personal, differing among individuals based on variations in body mass, stature, and the degree of physical exertion. One's exposure to direct sunlight has the potential to intensify the heat sensation, increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values remain especially vital for babies and toddlers. Kids are generally in more danger than adults because they perspire less. Their large skin surface area compared to their small bodies and the excessive heat due to their actions raises their risk.
When the body gets too warm, it perspires, leading to sweat evaporation which cools it down. In the presence of abundant moisture in the atmosphere, the cooling process through evaporation is hindered, causing the body to feel excessively warm. Heat disorders may be on the horizon when body temperatures rise from inadequate heat management.
Humidity
With an average relative humidity of 70%, July is the least humid month.Rainfall
In Johnston, during July, the rain falls for 17.5 days and regularly aggregates up to 2.44" (62mm) of precipitation. In Johnston, during the entire year, the rain falls for 149.8 days and collects up to 28.58" (726mm) of precipitation.Snowfall
April through November are months without snowfall in Johnston.Daylight
In July, the average length of the day is 14h and 8min.On the first day of the month, sunrise is at 6:20 am and sunset at 8:42 pm. On the last day of July, sunrise is at 6:38 am and sunset at 8:28 pm EDT.
Sunshine
The months with the most sunshine are June and July, with an average of 10.9h of sunshine.UV index
June through August, with an average maximum UV index of 7, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health risk from unprotected exposure to Sun's UV rays for average individuals.Note: A daily high UV index of 7 in July leads to these guidelines:
Stay clear of intense sun exposure. Solar protection is of utmost significance. The Sun's UV radiation is most potent between the hours of 10 a.m. and 4 p.m. Try to avoid direct sunlight during this time. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in July
Johnston, SC
- Average high temperature in July: 91.4°F
The warmest month (with the highest average high temperature) is July (91.4°F).
The month with the lowest average high temperature is January (52.7°F).
- Average low temperature in July: 72.5°F
The month with the highest average low temperature is July (72.5°F).
The coldest month (with the lowest average low temperature) is January (36.9°F).
Average pressure in July
Johnston, SC
- Average pressure in July: 30"Hg
The months with the highest atmospheric pressure are January, November and December (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.98"Hg).
Average wind speed in July
Johnston, SC
- Average wind speed in July: 5.6mph
The windiest months (with the highest average wind speed) are February and April (8.1mph).
The calmest month (with the lowest average wind speed) is August (5.2mph).
Average humidity in July
Johnston, SC
- Average humidity in July: 70%
The month with the highest relative humidity is December (76%).
The month with the lowest relative humidity is July (70%).
Average rainfall in July
Johnston, SC
- Average rainfall in July: 2.44"
The wettest month (with the highest rainfall) is December (3.03").
The driest month (with the least rainfall) is September (1.42").
Average rainfall days in July
Johnston, SC
- Average rainfall days in July: 17.5 days
The month with the highest number of rainy days is July (17.5 days).
The month with the least rainy days is November (7.8 days).
Average snowfall in July
Johnston, SC
- Average snowfall in July: 0"
The month with the highest snowfall is February (0.59").
The months with the least snowfall are April, May, June, July, August, September, October and November (0").
Average snowfall days in July
Johnston, SC
- Average snowfall days in July: 0 days
The months with the highest number of snowfall days are January and February (0.4 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in July /
Average sunshine in July
Johnston, SC
- Average daylight in July: 14h and 6min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in July: 10h and 54min
The months with the most sunshine are June and July (Average sunshine: 10h and 54min).
The month with the least sunshine is December (Average sunshine: 5h and 24min).
Average sunshine days in July
Johnston, SC
- Average sunshine days in July: 11.2 days
The month with the most sunshine days is October (21.8 days).
The month with the least sunshine days is July (11.2 days).
Average UV index in July
Johnston, SC
- Average UV index in July: 7
The months with the highest UV index are June, July and August (UV index 7).
The month with the lowest UV index is January (UV index 2).
Average cloud cover in July
Johnston, SC
- Average cloud cover in July: 28
The month with the most cloud cover is December (Cloud cover 41).
The month with the least cloud cover is October (Cloud cover 27).
Average visibility in July
Johnston, SC
- Average visibility in July: 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).
