What is the weather like in Aspen vs Rocky Mountain National Park in September?

In September, Aspen averages 22°C high / 6°C low with about 30 mm of rain; Rocky Mountain National Park averages 18°C high / 6°C low with about 41 mm.

Aspen vs Rocky Mountain National Park in September

Rocky Mountain National Park is the better pick in September — 90 vs 20 on SeasonMap's comfort score. Rocky Mountain National Park is cool, a little rain, clean air, while Aspen is nice, a little rain, clean air.

Aspen vs Rocky Mountain National Park — September climate, side by side

	🇺🇸 Aspen	🇺🇸 Rocky Mountain National Park
Comfort score	20/100 (F)	90/100 (S)
Feels-like high	20°C	15°C
Avg high / low	22° / 6°	18° / 6°
Rainfall	30 mm	41 mm
Rainy days	6	6
Humidity	55%	57%
Air quality (AQI)	44	40

Monthly climate normals (ERA5 reanalysis). Comfort scores are SeasonMap estimates.

Month by month

Aspen 🇺🇸 United Statesnice, a little rain, clean air · best January20
Rocky Mountain National Park 🇺🇸 United Statescool, a little rain, clean air · best August90

Aspen vs Rocky Mountain National Park in September — FAQ

Is September better in Aspen or Rocky Mountain National Park?: Rocky Mountain National Park is the better pick in September — 90 vs 20 on SeasonMap's comfort score. Rocky Mountain National Park is cool, a little rain, clean air, while Aspen is nice, a little rain, clean air.
What is the weather like in Aspen vs Rocky Mountain National Park in September?: In September, Aspen averages 22°C high / 6°C low with about 30 mm of rain; Rocky Mountain National Park averages 18°C high / 6°C low with about 41 mm.