Knoxville, TN weather in August
Knoxville is hot and humid in August, with some rain: highs average 88°F and nights drop to about 65°F. Rain falls on about 10 days. This is the peak of the warm season in Knoxville.
- Normal high
- 88°F
- Normal low
- 65°F
- Wet days
- 10
- 3.4 in total
- Muggy days
- 23
- dew point 65°F+
How August changes from start to finish
| August 1 | August 31 | |
|---|---|---|
| Normal high | 88°F | 87°F |
| Normal low | 66°F | 63°F |
| Chance of a wet day | 36% | 29% |
| Sunrise / sunset | 6:43 am / 8:40 pm | 7:06 am / 8:05 pm |
| Daylight | 14.0 h | 13.0 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Eastern Time).
A typical August day
- 6 am69°Fdew point 66°F
- 9 am75°Fdew point 68°F
- Noon83°Fdew point 67°F
- 3 pm85°Fdew point 66°F
- 6 pm83°Fdew point 66°F
- 9 pm76°Fdew point 67°F
NOAA hourly normals (local standard time) from Knoxville Mcghee Tyson Airport (11 mi away); average wind 5 mph.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F0 of 31
- Hot dayshigh 90°F or more11 of 31
- Muggy daysdaily mean dew point 65°F or more23 of 31
- Wet daysat least 0.01 in of rain or melted snow10 of 31
- Notable rainat least 0.10 in6 of 31
- Freezing nightslow 32°F or below0 of 31
- Snow on the groundsnow depth 1 in or more0 of 31
Average days per August, counted from daily records for each year 1991-2020.
Rain in August
Normal precipitation is 3.4 in; a dry August brings about 2.0 in and a wet one about 4.7 in (25th and 75th percentiles). About 2 days bring half an inch or more, and about 1 an inch or more.
How August varies from year to year
- Warmest August, 1991-20202007: average high 95°F
- Coolest August2004: average high 81°F
- Wettest August2020: 7.1 in
- Driest August2016: 0.6 in
- Highest reading102°F (August 17, 2007)
- Lowest reading51°F (August 24, 1997)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
August compared with July and September
| July | August | September | |
|---|---|---|---|
| Normal high | 88°F | 88°F | 83°F |
| Normal low | 66°F | 65°F | 59°F |
| Wet days | 12 | 10 | 9 |
| Comfortable days | 0 | 0 | 6 |
| Daylight | 14.3 h | 13.5 h | 12.4 h |
Highs change by 0°F from July and -5°F into September.
Nearby alternatives in August
- Warmer: Columbia, SC212 mi · high 94°F · 10 wet days
- Cooler: Gatlinburg, TN29 mi · high 82°F · 14 wet days
How Knoxville ranks in August
- Normal high169th warmest of 378 cities; 6th of 7 in Tennessee
- Wet days228th driest of 378
- Comfortable days217th most of 341
What to pack for Knoxville in August
- Light, breathable clothing – highs near 88°F and about 23 muggy days
- A rain jacket or umbrella – rain on about 10 days
Heating and cooling
August has 1 heating degree days and 352 cooling degree days (base 65°F), 7% of the year's total heating and cooling demand.
Questions
How hot is Knoxville in August?
The normal high is 88°F and the normal low is 65°F. From 1991 to 2020 the hottest August reading was 102°F (August 17, 2007).
Does it rain a lot in Knoxville in August?
About 10 days in August have at least 0.01 in of precipitation, and the normal total is 3.4 in. The wettest August in 1991-2020 was in 2020 (7.1 in); the driest was in 2016 (0.6 in).
Is August a good time to visit Knoxville?
August ranks 9th of 12 months on our comfort score for Knoxville (45 out of 100). It has almost no comfortable days and about 11 days at 90°F or hotter. The best months are April and October.
Where the numbers come from
- Temperature, rain and frost dates: Knoxville Exp Stn (USC00404946), 4.8 mi SSW of the city center, 830 ft (69 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Snowfall, snow depth and humidity and wind by hour: Knoxville Mcghee Tyson Airport (USW00013891), 11 mi SSW of the city center, 962 ft (63 ft higher than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Mc Ghee Tyson Airport (723260-13891), 11 mi SSW of the city center, 970 ft (71 ft higher than the city). Hourly observations, 1991-2020.
- Not available for this location: cloud cover (no station close enough or similar enough in elevation).