Great Smoky Mountains National Park
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Great Smoky Mountains National Park Weather in September

September in Great Smoky Mountains National Park brings high temperatures around 22°C (72°F) during the day, dropping to 10°C (50°F) at night, with quite a bit of rainfall expected, averaging around 136 mm (5.4 in) for the month.

Rainfall in Great Smoky Mountains National Park in September

Rain is expected on roughly 13 days, totalling around 136 mm (5.4 in) for the month. When it rains this month, it tends to come down fairly heavily. Showers can be substantial even if they don't last all day.

Temperature in Great Smoky Mountains National Park in September

Expect highs of 22°C (72°F) in Great Smoky Mountains National Park in September, with nights dropping to around 10°C (50°F). The days can feel warmer than the evenings, so packing for both parts of the day is a good idea. At 10°C (50°F) overnight, it can feel quite a bit cooler after dark. Worth packing something warmer for evenings, but the cooler temperatures are ideal for sleeping.

Sunshine in Great Smoky Mountains National Park in September

The city usually sees around 233 hours of sunlight, indicating many sunny days , a great month for sightseeing.

If your ideal day consists of dry skies and pleasant temperatures, May, June, August and September typically offer the best circumstances for Great Smoky Mountains National Park.

Great Smoky Mountains National Park Temperature in September

Min Temperature
10°C (50°F)
Max Temperature
22°C (72°F)
Chance of Rain
43%
Precipitation
136 mm (5.4 in)
Rainy days
13 days
Humidity
76% *
Sunshine
233 hours *
Percentage Sunshine
62% *
* Data from: Knoxville, the United States of America (54 KM, 34 Miles).

Great Smoky Mountains National Park Weather by Month

Pick a month to see the average temperature, rainfall and sunshine in Great Smoky Mountains National Park - and find the best time to visit.

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Great Smoky Mountains National Park typically drop from around 29°C (84°F) at the start of September to approximately 25°C (77°F) by the end. Nights are pleasant, with lows typically ranging from 13°C (55°F) to 19°C (66°F).

Average temperatures in September

Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in September

Historical weather records for Great Smoky Mountains National Park in September

Browse day-by-day weather records for Great Smoky Mountains National Park spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Great Smoky Mountains National Park historical weather extremes in September

According to our 50 years of weather records for Great Smoky Mountains National Park, the following extremes were recorded between 1976 and 2026.

  • The hottest September day on record in Great Smoky Mountains National Park reached 35°C (95°F) (September 5, 1998).
  • The coldest September day was on September 23, 1995, with a maximum of 12°C (54°F).
  • Nighttime temperatures dropped to 3°C (37°F) on September 28, 2022, marking the coldest September night on record.
  • The wettest September day on record brought 93 mm (3.7 in) of precipitation to Great Smoky Mountains National Park (September 15, 1989).

Best Places in the United States of America in September

Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in September →

perfect weather
pleasant
tolerable
unpleasant
poor

Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).

What to Wear in Great Smoky Mountains National Park in September

Pleasant temperatures in September mean you can pack light but flexibel pieces. Think cotton t-shirts, comfortable walking shorts, and one warmer layer for evenings. A light sweater or denim jacket works well. Prepare for significant rainfall with proper waterproof clothing and shoes. Don't forget sun protection, sunglasses, sunscreen, and a hat. These are all good ideas with this much sunshine.

What To Do in Great Smoky Mountains National Park in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

  • Cycling
    9/10
  • Walking
    9/10
  • Camping
    6/10
  • Outdoor sports
    9/10

Great Smoky Mountains National Park 3-Day Forecast

More climate data for Great Smoky Mountains National Park

Popular in September

Where to go in September - average daytime high across popular destinations.

Bucket list

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