Montana weather in September
One place stands in for Montana here — these are Bozeman's numbers, not a statewide average.
Based on 1 weather station, in Bozeman. One station — Bozeman speaks for the mountain valleys of southwest Montana, not for the plains that stretch east of the Rockies.
Bozeman & the Gallatin Valley
Highs near 71°, nights around 42°, and 1.4 in of rain in a typical September.
| Place | Highs / lows | Wet days | The short version |
|---|---|---|---|
| Bozeman | 71° / 42° | 4 | Blue afternoons, hard mornings, and gold up the canyons. |
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.