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's arrival brings an average high-temperature of a still tropical 88.3°F (31.3°C), slightly deviating from July's 89.4°F (31.9°C). Alton's nighttime temperature during August is consistently averaged at a refreshing 67.5°F (19.7°C).Heat index
For most parts of August, the heat index is computed to be a blisteringly hot 104°F (40°C). More preventive actions are needed, risk of heat exhaustion and heat cramps is significant. Prolonged activity may trigger heatstroke.Be aware that heat index ratings are designed for shaded locations and minor breezes. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', offers an insight into how hot it feels when we factor in moisture content. The impact of weather is personal, differing among a variety of people based on differences in body mass, height, and the level of physical exertion. When exposed to direct sunlight, it's possible for the heat index to increase by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are essentially critical for children. Youngsters are usually more at risk than adults, considering they sweat less. Additionally, their high skin surface area compared to their little bodies and their high heat production due to activity increases their risk.
By perspiring, the human body can shed its excessive warmth since evaporated sweat cools it off. Under high air temperature coupled with high humidity (high heat index), the body's perspiration is reduced, intensifying the sensation of heat. Overheating and potential dehydration arise when body heat gain eclipses its release capability.
Humidity
In Alton, the average relative humidity in August is 74%.Rainfall
In Alton, in August, it is raining for 15.8 days, with typically 2.8" (71mm) of accumulated precipitation. In Alton, during the entire year, the rain falls for 148 days and collects up to 35.39" (899mm) of precipitation.Snowfall
May through October are months without snowfall.Daylight
The average length of the day in August is 13h and 31min.On the first day of the month, sunrise is at 6:12 am and sunset at 8:11 pm. On the last day of August, in Alton, sunrise is at 6:36 am and sunset at 7:34 pm CDT.
Sunshine
The average sunshine in August is 10.1h.UV index
In August, the average daily maximum UV index is 6. A UV Index of 6 to 7 symbolizes a high health risk from exposure to the Sun's UV radiation for average individuals.Note: An average UV index of 6 in August transforms into this advice:
Stick with precautions and abide by sun safety procedures. Evading sunburn is essential. The Sun's UV radiation is most powerful between 10 a.m. and 4 p.m. To the extent possible, limit exposure to the direct sun during these hours. Tightly woven clothing, when worn loosely, shields effectively against the Sun.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How hot does it get in August?
What is the average humidity in August?
How much 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 many hours of sunshine does Alton have in August?
How high is the UV index in August?
Average temperature in August
Alton, MO
- Average high temperature in August: 88.3°F
The warmest month (with the highest average high temperature) is July (89.4°F).
The month with the lowest average high temperature is January (43.3°F).
- Average low temperature in August: 67.5°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 (28.4°F).
Average pressure in August
Alton, MO
- Average pressure in August: 29.97"Hg
The month with the highest atmospheric pressure is January (30.16"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed in August
Alton, MO
- Average wind speed in August: 5.3mph
The windiest months (with the highest average wind speed) are January, February, March and April (8.1mph).
The calmest months (with the lowest average wind speed) are July and August (5.3mph).
Average humidity in August
Alton, MO
- Average humidity in August: 74%
The months with the highest relative humidity are March and May (79%).
The month with the lowest relative humidity is October (72%).
Average rainfall in August
Alton, MO
- Average rainfall in August: 2.8"
The wettest month (with the highest rainfall) is May (4.25").
The driest month (with the least rainfall) is September (1.57").
Average rainfall days in August
Alton, MO
- Average rainfall days in August: 15.8 days
The month with the highest number of rainy days is May (16.5 days).
The month with the least rainy days is January (8.6 days).
Average snowfall in August
Alton, MO
- Average snowfall in August: 0"
The month with the highest snowfall is February (1.26").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days in August
Alton, MO
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is February (2.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in August /
Average sunshine in August
Alton, MO
- Average daylight in August: 13h and 3min
The month with the longest days is June (Average daylight: 14h and 36min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in August: 10h and 1min
The month with the most sunshine is June (Average sunshine: 10h and 24min).
The month with the least sunshine is February (Average sunshine: 4h and 48min).
Average sunshine days in August
Alton, MO
- Average sunshine days in August: 12.7 days
The month with the most sunshine days is December (19.6 days).
The month with the least sunshine days is May (12.3 days).
Average UV index in August
Alton, MO
- Average UV index in August: 6
The month with the highest UV index is June (UV index 7).
The months with the lowest UV index are January and December (UV index 2).
Average cloud cover in August
Alton, MO
- Average cloud cover in August: 31
The month with the most cloud cover is March (Cloud cover 49).
The month with the least cloud cover is June (Cloud cover 29).
Average visibility in August
Alton, MO
- Average visibility in August: 6mi
The months with the highest visibility are January, February, March, April, June, August, September, October, November and December (6mi).
The months with the lowest visibility are May and July (5mi).
Alton, Missouri, USA
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