Chattanooga, TN weather in September
Chattanooga is warm and often humid in September, with some rain: highs average 84°F and nights drop to about 64°F. Expect about 8 wet days.
- Normal high
- 84°F
- Normal low
- 64°F
- Wet days
- 8
- 4.2 in total
- Muggy days
- 11
- dew point 65°F+
How September changes from start to finish
| September 1 | September 30 | |
|---|---|---|
| Normal high | 88°F | 80°F |
| Normal low | 68°F | 58°F |
| Chance of a wet day | 28% | 26% |
| Sunrise / sunset | 7:14 am / 8:08 pm | 7:35 am / 7:27 pm |
| Daylight | 12.9 h | 11.9 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 September day
- 6 am65°Fdew point 62°F
- 9 am71°Fdew point 63°F
- Noon79°Fdew point 62°F
- 3 pm82°Fdew point 61°F
- 6 pm80°Fdew point 61°F
- 9 pm72°Fdew point 63°F
NOAA hourly normals (local standard time) from Chattanooga Lovell Airport (6 mi away); average wind 4 mph.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F5 of 30
- Hot dayshigh 90°F or more7 of 30
- Muggy daysdaily mean dew point 65°F or more11 of 30
- Wet daysat least 0.01 in of rain or melted snow8 of 30
- Notable rainat least 0.10 in5 of 30
- Freezing nightslow 32°F or below0 of 30
- Snow on the groundsnow depth 1 in or more0 of 30
Average days per September, counted from daily records for each year 1991-2020.
Rain in September
Normal precipitation is 4.2 in; a dry September brings about 1.9 in and a wet one about 5.9 in (25th and 75th percentiles). About 3 days bring half an inch or more, and about 1 an inch or more.
How September varies from year to year
- Warmest September, 1991-20202019: average high 94°F
- Coolest September1996: average high 79°F
- Wettest September2009: 12.4 in
- Driest September2019: 0.6 in
- Highest reading103°F (September 13, 2019)
- Lowest reading44°F (September 29, 2003)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
September compared with August and October
| August | September | October | |
|---|---|---|---|
| Normal high | 90°F | 84°F | 74°F |
| Normal low | 70°F | 64°F | 51°F |
| Wet days | 9 | 8 | 8 |
| Comfortable days | 0 | 5 | 16 |
| Daylight | 13.4 h | 12.4 h | 11.3 h |
Highs change by -6°F from August and -10°F into October.
Nearby alternatives in September
- Warmer: Montgomery, AL194 mi · high 89°F · 7 wet days
- Cooler: Gatlinburg, TN111 mi · high 78°F · 11 wet days
How Chattanooga ranks in September
- Normal high142nd warmest of 378 cities; 3rd of 7 in Tennessee
- Wet days194th driest of 378
- Comfortable days209th most of 342
Heating and cooling
September has 7 heating degree days and 276 cooling degree days (base 65°F), 6% of the year's total heating and cooling demand.
Questions
How hot is Chattanooga in September?
The normal high is 84°F and the normal low is 64°F. From 1991 to 2020 the hottest September reading was 103°F (September 13, 2019).
Does it rain a lot in Chattanooga in September?
About 8 days in September have at least 0.01 in of precipitation, and the normal total is 4.2 in. The wettest September in 1991-2020 was in 2009 (12.4 in); the driest was in 2019 (0.6 in).
Is September a good time to visit Chattanooga?
September ranks 7th of 12 months on our comfort score for Chattanooga (51 out of 100). It has about 5 comfortable days and about 7 days at 90°F or hotter. The best months are April and October.
Where the numbers come from
- Temperature, rain, snowfall, snow depth, frost dates and humidity and wind by hour: Chattanooga Lovell Airport (USW00013882), 6.2 mi E of the city center, 671 ft . NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: Lovell Field Airport (723240-13882), 6.3 mi E of the city center, 669 ft . Hourly observations, 1991-2020.
- Not available for this location: cloud cover (no station close enough or similar enough in elevation).