August weather forecastSaint Jacob, IL
August
Weather in August
August, the last month of the summer in Saint Jacob, is another warm month, with an average temperature fluctuating between 65.8°F (18.8°C) and 83.7°F (28.7°C).Temperature
In August, Saint Jacob experiences a barely noticeable shift in meteorological conditions, with average high-temperatures moving from 84.9°F (29.4°C) in July to a still warm 83.7°F (28.7°C). In August, Saint Jacob records an average nighttime temperature of 65.8°F (18.8°C).Heat index
The average heat index in August is computed to be a tropical 93.2°F (34°C). Adopt heightened preventive measures, heat exhaustion and heat cramps are probable. Persistent activity could lead to heatstroke.Heat index data is primarily for areas with shade and subjected to light winds. An exposure to direct sunlight may lift the heat index values by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'felt air temperature' or 'apparent temperature', comes about by integrating the temperature readings with the humidity levels. This effect is subjective, differing among individuals based on their physical activity and perception of heat, which can be influenced by factors like wind, clothing, and metabolic variances. 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 largely significant for babies and toddlers. Children often fail to understand the importance of rest and rehydration. Thirst is a late manifestation of dehydration - hence, it is crucial to stay hydrated, especially during ongoing physical activities.
Humidity
The months with the highest humidity are July and August, with an average relative humidity of 80%.Rainfall
In Saint Jacob, in August, during 9.7 rainfall days, 1.14" (29mm) of precipitation is typically accumulated. In Saint Jacob, Illinois, during the entire year, the rain falls for 110.6 days and collects up to 12.01" (305mm) of precipitation.Snowfall
In Saint Jacob, snow does not fall in April through September.Daylight
In Saint Jacob, the average length of the day in August is 13h and 38min.On the first day of August, sunrise is at 6:01 am and sunset at 8:09 pm. On the last day of the month, sunrise is at 6:28 am and sunset at 7:30 pm CDT.
Sunshine
In August, the average sunshine is 10.2h.UV index
May through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health hazard from unsafe exposure to UV radiation for the average person.Note: The maximum daily UV index, 6 in August, converts into the following recommendations:
Undertake protective measures and comply with sun safety rules. Shielding against skin and eye damage is essential. 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. Sunglasses that ward off UVA and UVB rays play a pivotal role in reducing solar eye damage.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Saint Jacob, IL
- Average high temperature in August: 83.7°F
The warmest month (with the highest average high temperature) is July (84.9°F).
The month with the lowest average high temperature is January (36.9°F).
- Average low temperature in August: 65.8°F
The month with the highest average low temperature is July (67.6°F).
The coldest month (with the lowest average low temperature) is January (23.7°F).
Average pressure in August
Saint Jacob, 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 (29.92"Hg).
Average wind speed in August
Saint Jacob, IL
- Average wind speed in August: 5.7mph
The windiest month (with the highest average wind speed) is January (9.8mph).
The calmest months (with the lowest average wind speed) are July and August (5.7mph).
Average humidity in August
Saint Jacob, IL
- Average humidity in August: 80%
The months with the highest relative humidity are July and August (80%).
The month with the lowest relative humidity is October (71%).
Average rainfall in August
Saint Jacob, IL
- Average rainfall in August: 1.14"
The wettest month (with the highest rainfall) is May (1.46").
The driest month (with the least rainfall) is February (0.55").
Average rainfall days in August
Saint Jacob, IL
- Average rainfall days in August: 9.7 days
The month with the highest number of rainy days is May (13.1 days).
The months with the least rainy days are January and December (5.9 days).
Average snowfall in August
Saint Jacob, IL
- Average snowfall in August: 0"
The month with the highest snowfall is December (0.94").
The months with the least snowfall are April, May, June, July, August and September (0").
Average snowfall days in August
Saint Jacob, IL
- Average snowfall days in August: 0 days
The months with the highest number of snowfall days are January and February (4.8 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 Jacob, IL
- Average daylight in August: 13h and 36min
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 30min).
- Average sunshine in August: 10h and 12min
The month with the most sunshine is June (Average sunshine: 10h and 36min).
The months with the least sunshine are January and February (Average sunshine: 4h and 36min).
Average sunshine days in August
Saint Jacob, IL
- Average sunshine days in August: 17.3 days
The month with the most sunshine days is December (21.8 days).
The month with the least sunshine days is July (14.5 days).
Average UV index in August
Saint Jacob, IL
- 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
Saint Jacob, IL
- Average cloud cover in August: 28
The months with the most cloud cover are January and February (Cloud cover 50).
The months with the least cloud cover are June, July, August and September (Cloud cover 28).
Average visibility in August
Saint Jacob, 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).





