Denver Weather in September

Denver at 5,280 feet (exactly one mile high) has a semi-arid climate with 300 days of sunshine annually. The Rocky Mountains 40 miles to the west dramatically influence weather — Chinook winds can raise temperatures 50°F in hours, and afternoon thunderstorms are nearly daily in summer. Snowstorms can be intense but melt quickly due to high altitude sun.

Excellent shoulder season — warm with fewer tourists in many destinations.