September is a good month at Yellowstone — it ranks 6th of the twelve here. Expect about 14% fewer visitors than July, the park's peak — 796,027 visits on average. Days run around 65°F by afternoon and 30°F at night, with 12.4 hours of daylight.
September against the park's best
| Month | Verdict | Avg. visits | vs. peak | High | Low | Snow | Daylight |
|---|---|---|---|---|---|---|---|
| September (this page) | Good | 796,027 | −14% | 65°F | 30°F | 0.9" | 12.4 h |
| May (best) | Excellent | 508,111 | −45% | 55°F | 29°F | 5.4" | 14.8 h |
| July (peak crowds) | Good | 922,896 | peak | 76°F | 39°F | 0" | 15.2 h |
Weather figures are for the Old Faithful area (7,300 ft) — the Old Faithful station. Visits are 2021–2025 averages; climate normals cover 1991–2020. Conditions vary across the park; check current status before you go.
Common questions
Is September a good time to visit Yellowstone?
Yes — a solid month, if not the very best. September ranks 6 of 12 at Yellowstone on crowds, weather, daylight, and access together.
How crowded is Yellowstone in September?
About 796,027 recreation visits on average — 14% below July, the park's peak.
How warm is Yellowstone in September?
Average highs around 65°F and lows around 30°F at the Old Faithful station.
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