Early autumn · Weather & things to do
Glacier National Park in September
Glacier National Park cools off: highs slip to 59°F (15°C), from 69°F in August, with lows of 37°F (3°C) and about 2.2 in (55 mm) of rain.
It scores 81/100 for comfort, 3rd of 12, which makes it a solid shoulder-season month.
- Avg high
- 59°F (15°C)
- Avg low
- 37°F (3°C)
- Rain
- 2.2 in (55 mm)
- Humidity
- 67%
- Cloud cover
- 55%
- Daylight
- ~12 h 20 min
- Comfort score
- 81/100 · Great
What September feels like
Highs near 59°F (15°C) make for comfortable sightseeing weather.
Mornings start much cooler: lows average 37°F (3°C), about 12°C (22°F) below the afternoon high.
About 2.2 in (55 mm) of rain falls in a typical year's September.
Plan around September
September is shoulder season: good weather, a step below the best months (July & August).
- Comfort slips from 95/100 in August to 81/100.
- September sits inside the Jun – Sep window our Glacier to Yellowstone route recommends.
What to pack for September
- A warm layer for eveningsnights drop to 37°F
- Comfortable walking shoesmost places below are best reached on foot or with short walks
What to do in Glacier National Park in September
With conditions on your side, the picks below favor time outside.
Glacier Park Boat Company Many Glacier Cruise
Historic wooden boats across Swiftcurrent and Lake Josephine with ranger-led walks.
Why now September scores 81/100 for comfort, good conditions for being outside.
Trail of the Cedars and Avalanche Lake Trail
Flat boardwalk through old cedars, continuing 2.3 miles to a lake ringed by waterfalls.
Why now Highs near 59°F and 2.2 in of monthly rain make this an easy outdoor pick.
Lake McDonald
Glacier's largest lake, famous for colored stones visible through clear water at Apgar.
Why now One to do outside while the weather is on your side.
Northern Lights Saloon
Log-cabin saloon next to the Mercantile, with a beer garden facing the peaks.
Russell's Fireside Dining Room
Lake McDonald Lodge dining room with regional dishes like bison and huckleberry desserts.
Nearby in September
- Banff in September~185 mi · highs 59°F, 2.7 in rain · similar daytime temperatures, about as wet
- Lake Louise in September~212 mi · highs 55°F, 3.1 in rain · 2°C (4°F) cooler by day, wetter
NASA POWER 2001–2025 monthly averages on a ~50 km grid. Comfort scores weigh temperature, rain, humidity and cloud: see how we score each month. Check a forecast before you go.
Glacier National Park in September: quick answers
Is September a good time to visit Glacier National Park?
It's a good shoulder-season choice, scoring 81/100 against a best of 97 in July & August. Expect highs of 59°F (15°C) and 2.2 in (55 mm) of rain. September is inside the Jun – Sep window our Glacier to Yellowstone route recommends.
How cold is Glacier National Park in September?
Average highs are 59°F (15°C) and average lows 37°F (3°C), making it the 4th-warmest month by daytime highs.
Does it rain a lot in Glacier National Park in September?
Not much: about 2.2 in (55 mm) of rain falls across September on average, the 3rd-driest month of the year. The annual total is about 31.6 in (802 mm).
What should I pack for Glacier National Park in September?
Bring a warm layer for evenings (nights drop to 37°F) and comfortable walking shoes (most places below are best reached on foot or with short walks).
More on Glacier National Park
Routes in season in September
- Glacier to Yellowstone Jun – Sep
Planning Glacier National Park in September?
Plan it together in TripsCircle: one itinerary, one shared packing list and costs split as you go.