Early autumn · Weather & things to do
Black Hills in September
Black Hills cools off: highs slip to 70°F (21°C), from 80°F in August, with lows of 44°F (6°C) and about 1.6 in (40 mm) of rain.
At 96/100 for comfort (the top score of the year), it's one of the best months to visit.
- Avg high
- 70°F (21°C)
- Avg low
- 44°F (6°C)
- Rain
- 1.6 in (40 mm)
- Humidity
- 55%
- Cloud cover
- 43%
- Daylight
- ~12 h 17 min
- Comfort score
- 96/100 · Great
What September feels like
Highs settle around 70°F (21°C), warm enough for short sleeves most of the day.
There's a big swing between day and night, about 15°C (27°F), so mornings and evenings feel much cooler than the afternoon.
About 1.6 in (40 mm) of rain falls in a typical year's September.
Plan around September
September is one of Black Hills's best months on the climate data.
- Last warm month for a while: October highs fall to 52°F.
- Last of the best-scoring months: by October, the score drops to 72/100.
- Comfort holds steady from August (94 → 96/100).
- September sits inside the May – Sep window our Dakotas Badlands & Black Hills route recommends.
What to pack for September
- Light, breathable clotheshighs average 70°F
- A warm layer for eveningsnights drop to 44°F
- Comfortable walking shoesmost places below are best reached on foot or with short walks
What to do in Black Hills in September
September is good outdoor weather here, so these picks lean toward the open air.
Sylvan Lake
Granite-ringed lake with an easy 1-mile shoreline loop and boulder scrambles.
Why now September scores 96/100 for comfort, good conditions for being outside.
Mount Rushmore National Memorial
Four presidents carved in granite, with the Presidential Trail at the base.
Why now Highs near 70°F and 1.6 in of monthly rain make this an easy outdoor pick.
Iron Mountain Road
Winding road with pigtail bridges and tunnels that frame Mount Rushmore.
Why now One to do outside while the weather is on your side.
Needles Highway
14-mile road through granite spires and one-lane tunnels, including the Needles Eye.
Naughti Wines
Hill City tasting room on Hwy 385 pouring its own wines plus Sick-N-Twisted beers, with a patio and firepit.
Nearby in September
- Badlands National Park in September~64 mi · highs 78°F, 1.4 in rain · 5°C (8°F) warmer by day, about as wet
- Medora in September~217 mi · highs 74°F, 1.9 in rain · 2°C (4°F) warmer by day, about as wet
- Rocky Mountain NP in September~259 mi · highs 63°F, 1.7 in rain · 4°C (7°F) cooler by day, about as wet
- Denver in September~287 mi · highs 82°F, 1.4 in rain · 6°C (12°F) warmer by day, about as wet
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.
Black Hills in September: quick answers
Is September a good time to visit Black Hills?
Yes. On the climate data it's one of the best months, scoring 96/100. Expect highs of 70°F (21°C) and 1.6 in (40 mm) of rain. September is inside the May – Sep window our Dakotas Badlands & Black Hills route recommends.
How hot is Black Hills in September?
Average highs are 70°F (21°C) and average lows 44°F (6°C), making it the 4th-warmest month by daytime highs.
Does it rain a lot in Black Hills in September?
Not much: about 1.6 in (40 mm) of rain falls across September on average, the 6th-wettest month of the year. The annual total is about 19.2 in (487 mm).
What should I pack for Black Hills in September?
Bring light, breathable clothes (highs average 70°F), a warm layer for evenings (nights drop to 44°F) and comfortable walking shoes (most places below are best reached on foot or with short walks).
More on Black Hills
Routes in season in September
- Dakotas Badlands & Black Hills May – Sep
Planning Black Hills in September?
Bring the crew into one shared trip: vote on dates, build the day-by-day plan, split costs and share one packing list.