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
Saint Johns's shift from July to August is accompanied by an average high-temperature of a warm 85.5°F (29.7°C), a slight deviation from 87.3°F (30.7°C). Saint Johns's temperature drops to an average low of 66°F (18.9°C) during the nights of August.Heat index
The heat index value for August is estimated at a torrid 96.8°F (36°C). Undertake additional precautions, heat cramps and heat exhaustion could happen. Heatstroke could occur from sustained activity.When assessing, remember that heat index measurements are for light winds and shaded spots. Exposure to the sun directly might heighten the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'real feel' or 'apparent temperature', is a calculated temperature value of how hot it feels when the moisture in the air is factored in. The effect is personal, with varied weather perceptions among individuals due to differences in body mass, stature, and physical activity. Always consider that direct sunlight exposure might heighten the heat's effects, pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are particularly relevant to children. Juveniles often do not understand the need to recuperate and rehydrate. Thirst is a delayed symptom of dehydration - hence, it is vital to maintain hydration, particularly during ongoing physical activities.
When temperatures rise, the human body turns to perspiration, using the cooling power of evaporating sweat. When relative humidity increases, the body's capacity to evaporate heat decreases, leading to a heightened sense of warmth. As body temperatures escalate without effective heat release, one might face dehydration threats.
Humidity
In Saint Johns, the average relative humidity in August is 77%.Rainfall
In Saint Johns, in August, it is raining for 14 days, with typically 2.8" (71mm) of accumulated precipitation. In Saint Johns, during the entire year, the rain falls for 147.6 days and collects up to 29.17" (741mm) of precipitation.Snowfall
In Saint Johns, snow does not fall in May through October.Daylight
In August, the average length of the day is 13h and 35min.On the first day of the month, sunrise is at 6:00 am and sunset at 8:05 pm. On the last day of August, in Saint Johns, sunrise is at 6:26 am and sunset at 7:27 pm CDT.
Sunshine
The average sunshine in August is 10.1h.UV index
The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index reading of 6 to 7 represents a high health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: A typical high UV index of 6 in August suggests the following recommendations:
Endorse precautions and be consistent with sun safety guidelines. Preventing sunburn is paramount. Limit your exposure to the sun's UV radiation, which is strongest between 10 a.m. and 4 p.m., and note that parasols or canopies may not provide full sun protection. Protect your eyes, ears, face, and neck from the Sun by wearing a wide-brimmed hat.
Frequently asked questions
How hot does it get in Saint Johns in August?
What is the average humidity in August in Saint Johns?
How much does it rain in Saint Johns in August?
When it does not snow in Saint Johns?
How many hours of daylight does Saint Johns have in August?
What time are sunrise and sunset in August in Saint Johns?
How many hours of sunshine does Saint Johns have in August?
What are the months with the highest UV index in Saint Johns?
How high is the UV index in August in Saint Johns?
Average temperature in August
Saint Johns, IL
- Average high temperature in August: 85.5°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 (38.8°F).
- Average low temperature in August: 66°F
The month with the highest average low temperature is July (68.7°F).
The coldest month (with the lowest average low temperature) is January (25.7°F).
Average pressure in August
Saint Johns, IL
- Average pressure in August: 29.98"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in August
Saint Johns, IL
- Average wind speed in August: 5.8mph
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 August
Saint Johns, IL
- Average humidity in August: 77%
The month with the highest relative humidity is May (79%).
The month with the lowest relative humidity is October (71%).
Average rainfall in August
Saint Johns, IL
- Average rainfall in August: 2.8"
The wettest month (with the highest rainfall) is April (3.58").
The driest month (with the least rainfall) is January (1.5").
Average rainfall days in August
Saint Johns, IL
- Average rainfall days in August: 14 days
The month with the highest number of rainy days is May (17 days).
The month with the least rainy days is December (8.2 days).
Average snowfall in August
Saint Johns, IL
- Average snowfall in August: 0"
The month with the highest snowfall is February (1.5").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in August
Saint Johns, IL
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is January (5.4 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in August /
Average sunshine in August
Saint Johns, IL
- Average daylight in August: 13h and 4min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).
- Average sunshine in August: 10h and 1min
The month with the most sunshine is July (Average sunshine: 10h and 30min).
The month with the least sunshine is January (Average sunshine: 4h and 36min).
Average sunshine days in August
Saint Johns, IL
- Average sunshine days in August: 14.7 days
The months with the most sunshine days are October and November (19.5 days).
The month with the least sunshine days is May (11.4 days).
Average UV index in August
Saint Johns, IL
- Average UV index in August: 6
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, November and December (UV index 2).
Average cloud cover in August
Saint Johns, IL
- Average cloud cover in August: 29
The months with the most cloud cover are January and February (Cloud cover 50).
The month with the least cloud cover is June (Cloud cover 28).
Average visibility in August
Saint Johns, IL
- 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).
Saint Johns, Illinois, USA
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