August weather forecast
Knoxville, TN

Heatwaves start to subside, as Knoxville's August weather sees a slight dip in temperature compared to July. The transition month from peak summer to early fall is marked by hot but bearable climates. Though rainfall is at annual low, the decreased humidity ensures an enjoyable outdoor setting. August serves as a period of gradual cold anticipation, setting the stage for fall in Knoxville. The month's weather still accommodates outdoor activities, making it an idyllic time for picnics and recreational pursuits.

Temperature

August experiences an average high-temperature of a still tropical 88.2°F (31.2°C), barely different from July's 88.9°F (31.6°C). Knoxville documents a substantial shift from daytime warmth, recording an average nighttime temperature of 65.5°F (18.6°C) in August.

Heat index

In August, the average heat index is computed to be a sweltering 100.4°F (38°C). Adopt heightened safety measures, heat cramps and heat exhaustion may occur. Sustained activity might cause heatstroke.
Heat index details are generally centered around shaded locations and a mild breeze. Heat index values may rise by up to 15 Fahrenheit (8 Celsius) degrees when exposed to direct sunlight.
Note: The heat index, also known as 'apparent temperature' or 'felt air temperature', is an estimation of the warmth sensation when considering humidity levels. An individual's perception of weather can be swayed by a variety of elements including metabolic differences, pregnancy status, and their level of physical exertion. Be mindful that being in direct sunlight might mean feeling hotter, with the heat index rising by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Typically, young kids are at a higher risk than adults since they sweat less. Also, the larger skin surface in proportion to their small bodies and the heightened heat production due to their active nature adds to their vulnerability.
The body's innate mechanism to counteract overheating is through perspiration, as it leverages the cooling effects of sweat evaporation. Heightened relative humidity interferes with the body's usual cooling mechanism by reducing evaporation, subsequently decreasing the body's cooling rate and increasing the sensation of heat. As the body gains more heat than it can dissipate, there's a risk of increasing temperatures and resultant overheating.

Humidity

With an average relative humidity of 70%, August is the least humid month.

Rainfall

In Knoxville, in August, during 14.3 rainfall days, 2.01" (51mm) of precipitation is typically accumulated. Throughout the year, there are 148.9 rainfall days, and 29.57" (751mm) of precipitation is accumulated.

Snowfall

May through October are months without snowfall.

Daylight

In August, the average length of the day is 13h and 29min.
On the first day of the month, sunrise is at 6:43 am and sunset at 8:40 pm. On the last day of August, sunrise is at 7:07 am and sunset at 8:04 pm EDT.

Sunshine

The average sunshine in August is 9.9h.

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 exposure to the Sun's UV rays for ordinary individuals.
Note: The daily high UV index of 6 in August translates into this advice:
Guard oneself from overexposure. Defence against sun injury is vital. The Sun's UV radiation is most potent between the hours of 10 a.m. and 4 p.m. Try to avoid direct sunlight during this time. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.