Grand Teton National Park weather in September
September in Grand Teton National Park: nice, a little rain, with clean air — an excellent time to visit.
#4 of 12 months in Grand Teton National Park · #132 of 604 destinations to visit in September · comfort 87/100 (tier A)
Updated June 2026 · climate normals from ERA5 reanalysis
Grand Teton National Park climate normals — September
| Daytime high | 19°C / 67°F | 😎 nice |
|---|---|---|
| Nighttime low | 5°C / 42°F | |
| Feels like (high) | 17°C / 63°F | |
| Rainfall | 62 mm / 2.4 in | 🌦 some rain |
| Rainy days | 9 days | |
| Humidity | 63% | 💧 humid |
| Dew point | 4°C / 39°F | |
| Sunshine | 10.6 h/day | |
| Daylight | 12.5 h | |
| Wind | 13 km/h / 8 mph | |
| Snowfall | 5.5 cm / 2.2 in | |
| Air quality (US AQI) | 40 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Where is Grand Teton National Park?
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Grand Teton National Park in September — FAQ
- Is September a good time to visit Grand Teton National Park?
- September in Grand Teton National Park: nice, a little rain, with clean air — an excellent time to visit. It ranks #4 of 12 months for Grand Teton National Park on SeasonMap's comfort score (87/100).
- What is the weather like in Grand Teton National Park in September?
- In September, Grand Teton National Park averages a daily high of 19.4°C and a low of 5.3°C, with about 61.7 mm of rain over roughly 9.2 rainy days.
- What is the air quality in Grand Teton National Park in September?
- Grand Teton National Park has a mean US Air Quality Index of about 40 in September.
- Does it snow in Grand Teton National Park in September?
- Grand Teton National Park sees roughly 5.5 cm of snowfall in September.