Wyoming weather in September
The state broadly agrees with itself in September: afternoons run 69° in Yellowstone and 68° in Jackson Hole, with everywhere else in between.
Based on 2 weather stations. Two stations, both in the mountainous northwest corner where visitors go — the high plains that make up most of Wyoming aren’t measured here.
Jackson Hole & the Tetons
Highs near 68°, nights around 33°, and 1.6 in of rain in a typical September.
| Place | Highs / lows | Wet days | The short version |
|---|---|---|---|
| Jackson Hole | 68° / 33° | 4 | Aspens turn, crowds thin, and the frost returns nightly. |
Yellowstone Country
Highs near 69°, nights around 39°, and 1.2 in of rain in a typical September.
| Place | Highs / lows | Wet days | Snow | The short version |
|---|---|---|---|---|
| Yellowstone | 69° / 39° | 4 | 0.6 in | Bugling elk, thinner traffic, and frost on the boardwalks. |
Each place above has its own page for the full story — what the month feels like, what to pack, and whether the timing is right.