The weather in Wyoming in September is very cold with temperatures between 3°C and 16°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Wyoming during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
You can expect a few days of snow in Wyoming during September. It’s important to get out your snow boots and warm mittens to stay warm while you explore Wyoming.
Our weather forecast can give you a great sense of what weather to expect in Wyoming in September 2025.
If you’re planning to visit Wyoming in the near future, we highly recommend that you review the 14 day weather forecast for Wyoming before you arrive.