Weather in September 2025

Keystone weather in September 2025

°C °F

The average weather in Keystone in September

The weather in Keystone in September is hot. The average temperatures are between 21°C and 27°C.

As it is almost never rain during September in Keystone the weather is perfect for hanging out outside and exploring all that Keystone has to offer.

Our weather forecast can give you a great sense of what weather to expect in Keystone in September 2025.

If you’re planning to visit Keystone in the near future, we highly recommend that you review the 14 day weather forecast for Keystone before you arrive.

Temperatures
27° / 21°
Rainy Days
0
Snowy Days
0
Dry Days
30
Rainfall
12
mm
Sun Hours
11.3
Hrs

Explore the weather in Keystone in other months

Keystone annual weather

Month Temperatures Rainy Days Dry Days Snowy Days Rainfall Weather More details
January 20° / 13° 3 28 0 61 mm
Good
February 20° / 12° 2 26 0 55 mm
Good
March 20° / 13° 2 29 0 37 mm
Good
April 21° / 14° 1 29 0 16 mm
Good
May 22° / 15° 1 31 0 9 mm
Good
June 24° / 17° 0 30 0 5 mm
Perfect
July 26° / 19° 1 30 0 16 mm
Perfect
August 27° / 20° 0 31 0 12 mm
Perfect
September 27° / 21° 0 30 0 12 mm
Perfect
October 25° / 19° 1 30 0 17 mm
Perfect
November 23° / 15° 1 29 0 24 mm
Perfect
December 19° / 12° 2 29 0 61 mm
Good

Weather in Keystone in September - FAQ

What is the average temperature in Keystone in September?
The average temperature in Keystone in September is 21/27° C.
What is the chance of rain in Keystone in September?
On average, there are 0 rainy days in Keystone during September.
Weather wise, is September a good time to visit Keystone?
The weather in Keystone in September is perfect.
Can it snow in Keystone in September?
On average, there are 0 snowy days in Keystone in September.
More about the weather in Keystone