August weather forecast
Harrisburg, IL

August in Harrisburg, Illinois witnesses the grandeur of a typical late summer. Temperatures remain comparably high, ranging from 66°F (18.9°C) to 85.6°F (29.8°C), albeit a slight dip from July. The hot and sunny weather forms the perfect backdrop for enjoying summer festivities and water sports, although the scorching sun might call for necessary precautions. Even though rainfall occurrences are relatively low, they do offer a refreshing change from the enduring heat. As August concludes, temperatures start to decline, marking the imminent arrival of Autumn.

Temperature

August's arrival registers an average high-temperature of a warm 85.6°F (29.8°C), closely aligning with the temperature of the previous month. The average temperature during August nights dips to a refreshing 66°F (18.9°C).

Heat index

In August, the heat index is evaluated at a very hot 96.8°F (36°C). Implement more preventive measures, heat cramps and heat exhaustion are probable. Heatstroke might result from extended activity.
The heat index's values are generally associated with conditions in shade and light breezes. Direct sunlight exposure may cause a 15 Fahrenheit (8 Celsius) degrees rise in the heat index.
Note: The heat index, also known as 'real feel' or 'feels like', arises from combining readings of air temperature and relative moisture content. Physical activity, clothing, and metabolic variations are additional factors that impact an individual's perception of temperature. One should be aware that direct sunshine can amplify the perceived temperature, raising the heat index by as much as 15 Fahrenheit (8 Celsius) degrees. Heat index values are quite important for children. Young ones are generally at greater risk than adults due to their limited sweating ability. In addition, their large skin surface relative to their small bodies and higher heat production from their activities add to their vulnerability.
Perspiration is the human body's physiological response to high temperatures and is an attempt to lower body temperature through evaporation of sweat. In circumstances of high air temperature and humidity (high heat index), the body's perspiration is restricted, heightening the feeling of warmth. Potential thermal conditions emerge as the body's heat gain outpaces its cooling mechanisms.

Humidity

In August, the average relative humidity is 76%.

Rainfall

In August, the rain falls for 13.8 days. Throughout August, 2.52" (64mm) of precipitation is accumulated. In Harrisburg, during the entire year, the rain falls for 158.6 days and collects up to 36.02" (915mm) of precipitation.

Snowfall

May through September are months without snowfall.

Daylight

In August, the average length of the day is 13h and 34min.
On the first day of the month, sunrise is at 5:58 am and sunset at 8:02 pm. On the last day of August, sunrise is at 6:24 am and sunset at 7:24 pm CDT.

Sunshine

In Harrisburg, Illinois, the average sunshine in August is 10.3h.

UV index

The months with the highest UV index are May through August, with an average maximum UV index of 6. A UV Index estimate of 6 to 7 represents a high health hazard from exposure to the Sun's UV radiation for average individuals.
Note: A maximum high UV index of 6 in August translates into the following recommendations:
Employ safeguards and advocate sun safety protocols. Shielding against skin and eye damage is crucial. Avoid direct sunlight between the hours of 10 a.m. and 4 p.m., when UV radiation is at its peak. Keep in mind that shade structures may not provide complete protection. Wearing sunglasses with both UVA and UVB protection effectively reduces sun-induced eye damage.