‹ Yellowstone weather by month
Typical September weather
Yellowstone
Wyoming · September
69° days
39° nights
about 4 rainy days · 12½ hours of daylight
What to pack
- Sweater
- Sunscreen
- Layers
What September feels like
The elk rut runs through September and the bulls take over the lawns at Mammoth — rangers set out cones and keep people back, and the bugling carries through the whole village after dark. Most park lodges begin closing in the second half of the month, so take what is left early.
Expect about 4 days with real rain — enough to notice, not enough to plan around.
The numbers
| Typical high | 69° |
|---|---|
| Typical low | 39° |
| Days with real rain | 4 |
| Total rain | 1.2 in |
| Snowfall | 0.6 in |
| Sunrise / sunset (mid-month) | 7:02 am / 7:33 pm |