Contents
- Weather in August
- Frequently asked questions
- Average temperature in August
- Average pressure in August
- Average wind speed in August
- Average humidity in August
- Average rainfall in August
- Average rainfall days in August
- Average snowfall in August
- Average snowfall days in August
- Average daylight in August
- Average sunshine in August
- Average sunshine days in August
- Average UV index in August
- Average cloud cover in August
- Average visibility in August
Weather in August
Temperature
August welcomes an average high-temperature of a still hot 90.1°F (32.3°C), not much different from the preceding month. Johnston experiences an average low-temperature of 71.2°F (21.8°C) in month of August.Heat index
The heat index value during August is calculated to be a scorching 107.6°F (42°C). Implement additional safety measures to avoid heat cramps and heat exhaustion. Persistent activity might trigger heatstroke.Take into consideration that the heat index values are calculated for shade and light wind conditions. Under direct sunshine, the heat index values might be elevated by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'feels like', blends air temperature and moisture content to represent the felt temperature to humans. The impression of weather on a person can be swayed by additional aspects, including metabolic variations, pregnancy, and activity levels. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly important for children. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.
To cool down, the human body relies on perspiration, a process where excessive heat is eliminated as sweat evaporates. When there is an excess of moisture in the atmosphere, the efficiency of the evaporation process is lessened, leading to less efficient body cooling and a sensation of overheating. When heat surpasses the body's release mechanisms, dehydration and overheating risks become pronounced.
Humidity
In Johnston, the average relative humidity in August is 72%.Rainfall
In Johnston, during August, the rain falls for 16.2 days and regularly aggregates up to 2.87" (73mm) 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.Daylight
In Johnston, the average length of the day in August is 13h and 22min.On the first day of August in Johnston, sunrise is at 6:39 am and sunset at 8:27 pm. On the last day of the month, sunrise is at 7:00 am and sunset at 7:53 pm EDT.
Sunshine
The average sunshine in August is 10.4h.UV index
The months with the highest UV index are June through August, with an average maximum UV index of 7. A UV Index estimate of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for the average person.Note: In August, an average UV index of 7 transforms into the following instructions:
Implement preventive steps and embrace sun safety standards. Protection from skin and eye distress is compulsory. UV radiation from the Sun is most intense between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot is it in August?
What is the average humidity in August?
How many days does it rain in August?
When it does not snow?
What is the average length of the day in August?
What time are sunrise and sunset in August?
How long on average sun shines in August?
What is the month with the highest UV index?
How high is the UV index in August?
Average temperature in August
Johnston, SC
- Average high temperature in August: 90.1°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 August: 71.2°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 August
Johnston, SC
- Average pressure in August: 29.99"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 August
Johnston, SC
- Average wind speed in August: 5.2mph
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 August
Johnston, SC
- Average humidity in August: 72%
The month with the highest relative humidity is December (76%).
The month with the lowest relative humidity is July (70%).
Average rainfall in August
Johnston, SC
- Average rainfall in August: 2.87"
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 August
Johnston, SC
- Average rainfall days in August: 16.2 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 August
Johnston, SC
- Average snowfall in August: 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 August
Johnston, SC
- Average snowfall days in August: 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 August /
Average sunshine in August
Johnston, SC
- Average daylight in August: 13h and 2min
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 August: 10h and 2min
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 August
Johnston, SC
- Average sunshine days in August: 12.4 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 August
Johnston, SC
- Average UV index in August: 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 August
Johnston, SC
- Average cloud cover in August: 31
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 August
Johnston, SC
- Average visibility in August: 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, South Carolina, USA
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