Best Time Of The Year. July and November are good months to book flights. They tend to be months when other people are not planning their holidays, so they feature a low demand for airline tickets and consequent low prices. September, after the summer holidays, and January, after Christmas and Thanksgiving holidays, are months to avoid.
Weather in Denver in September. The average maximum daytime temperature in Denver in September is a warm 25Â°C (77Â°F). There are usually 9 hours of bright sunshine each day, which represents 73% of the 12 hours of daylight. Expect 30mm (1.2 inches) of rainfall across the whole of September with 7 days with some rain falling.
1.2. The highest average temperature in Denver is July at 74 degrees. The coldest average temperature in Denver is December at 28.5 degrees. The most monthly precipitation in Denver occurs in August with 2.7 inches.The Denver weather information is based on the average of the previous 3-7 years of data.Loading...he most monthly precipitation in Denver occurs in August with 2.7 inches. The Denver weather information is based on the average of the previous 3-7 years of data.