Keystone Weather in September
Keystone in September sees high daytime temperatures of 23°C (73°F) and nighttime lows of 8°C (46°F). Moderate rainfall is typical, with around 35 mm (1.4 in) for the month.
Rainfall in Keystone in September
You can expect rain on around 7 days based on historical patterns, with 35 mm (1.4 in) average for the month. Rain is scarce this month and when it does fall, it tends to be light. Unlikely to disrupt plans significantly.
Temperature in Keystone in September
September tends to be one of the perfect months in Keystone, with 23°C (73°F) in the afternoon and 8°C (46°F) overnight. This gives the month a fairly typical daily rhythm, with warmer afternoons and more comfortable nights. Nights drop to 8°C (46°F). Cold nights like these are actually great for sleeping well, as long as you have a warm enough duvet.If your ideal day consists of dry skies and pleasant temperatures, June, July, August and September typically offer the best circumstances for Keystone.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Keystone's climate page.
Keystone Temperature in September
Min Temperature
8°C (46°F)
Max Temperature
23°C (73°F)
Chance of Rain
22%
Precipitation
35 mm (1.4 in)
Rainy days
7 days
Best Places in the United States of America in September
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Keystone in September
Pleasant temperatures in September mean you can pack light but flexibel pieces. Think cotton t-shirts, comfortable walking shorts, and one warmer layer for evenings. A light sweater or denim jacket works well. Pack a light rain jacket or compact umbrella for occasional showers.What To Do in Keystone in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Keystone's climate page.
See the full Keystone climate overview or explore weather in the United States of America.
