August weather forecastGrain Valley, MO
August
Weather in August
August, the last month of the summer in Grain Valley, is another warm month, with an average temperature varying between 84.6°F (29.2°C) and 65.8°F (18.8°C).Temperature
The average high-temperature during August is a warm 84.6°F (29.2°C), almost matching the conditions of the preceding month. Throughout the month of August, Grain Valley witnesses an average temperature of 65.8°F (18.8°C).Heat index
During August, the heat index is calculated to be a hot 93.2°F (34°C). Additional precautions are required to avert heat cramps and heat exhaustion. Persistent activity may culminate in heatstroke.Keep in mind the heat index values are meant for areas in shade and with light wind. Heat index values may be hiked up by 15 Fahrenheit (8 Celsius) degrees under direct sunshine.
Note: The heat index, also known as 'feels like' or 'real feel', evaluates the perceived heat by adding the effect of moisture in the air. The individual's impression of temperature can be shaped by additional aspects such as metabolic variations, physical activity, and clothing. In direct sunlight, the heat's impact can be heightened, potentially leading to an increase in the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are especially crucial for babies and toddlers. In general, children are more at risk than adults because they sweat less. Furthermore, the large skin surface compared to their small bodies and the high heat production due to their actions contribute to this vulnerability.
Humidity
The average relative humidity in August is 76%.Rainfall
In August, the rain falls for 14.3 days. Throughout August, 2.91" (74mm) of precipitation is accumulated. In Grain Valley, during the entire year, the rain falls for 136.1 days and collects up to 28.78" (731mm) of precipitation.Snowfall
In Grain Valley, snow does not fall in June through September.Daylight
The average length of the day in August is 13h and 38min.On the first day of the month, sunrise is at 6:18 am and sunset at 8:27 pm. On the last day of August, sunrise is at 6:45 am and sunset at 7:48 pm CDT.
Sunshine
In August, the average sunshine is 10h.UV index
The months with the highest UV index are May through August, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high health vulnerability from unprotected exposure to Sun's UV rays for the average person.Note: A maximum UV index of 6 in August translates into the following recommendations:
Fend off overexposure. Sun protection is vital. The Sun's UV radiation is at its strongest between the hours of 10 a.m. and 4 p.m. Minimize direct exposure to the sun during this period. To best shield against UV radiation, choose sun-safe garments and dependable sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Grain Valley, MO
- Average high temperature in August: 84.6°F
The warmest month (with the highest average high temperature) is July (86.4°F).
The month with the lowest average high temperature is January (37°F).
- Average low temperature in August: 65.8°F
The month with the highest average low temperature is July (68.4°F).
The coldest month (with the lowest average low temperature) is January (22.8°F).
Average pressure in August
Grain Valley, MO
- Average pressure in August: 29.96"Hg
The month with the highest atmospheric pressure is January (30.17"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed in August
Grain Valley, MO
- Average wind speed in August: 6.3mph
The windiest months (with the highest average wind speed) are February and March (9.9mph).
The calmest month (with the lowest average wind speed) is August (6.3mph).
Average humidity in August
Grain Valley, MO
- Average humidity in August: 76%
The months with the highest relative humidity are May and June (79%).
The month with the lowest relative humidity is October (70%).
Average rainfall in August
Grain Valley, MO
- Average rainfall in August: 2.91"
The wettest month (with the highest rainfall) is May (4.13").
The driest month (with the least rainfall) is January (1.06").
Average rainfall days in August
Grain Valley, MO
- Average rainfall days in August: 14.3 days
The month with the highest number of rainy days is May (17.6 days).
The month with the least rainy days is January (5.2 days).
Average snowfall in August
Grain Valley, MO
- Average snowfall in August: 0"
The month with the highest snowfall is February (3.9").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days in August
Grain Valley, MO
- Average snowfall days in August: 0 days
The month with the highest number of snowfall days is February (6.6 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight in August /
Average sunshine in August
Grain Valley, MO
- Average daylight in August: 13h and 36min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in August: 10h and 0min
The months with the most sunshine are June and July (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 5h and 0min).
Average sunshine days in August
Grain Valley, MO
- Average sunshine days in August: 13.9 days
The month with the most sunshine days is December (21.8 days).
The month with the least sunshine days is May (10.8 days).
Average UV index in August
Grain Valley, MO
- Average UV index in August: 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, November and December (UV index 2).
Average cloud cover in August
Grain Valley, MO
- Average cloud cover in August: 28
The month with the most cloud cover is March (Cloud cover 48).
The month with the least cloud cover is July (Cloud cover 27).
Average visibility in August
Grain Valley, MO
- 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).





