DENVER — Well, September has arrived — summer 2023 was kind of a soggy dud, wasn’t it? — and things will start to change, but it looks like we'll go into a warmer-than-usual fall with an unprecedentedly strong El Nino in effect.
Typically, September is one of the nicest months of the year in Colorado. It's that third bowl of porridge, just right!
Some of the highlights:
- Big snow storms don’t happen often, but high mountains often get snow in September.
- September brings an end to most of the thunderstorms in Colorado.
- Beautiful fall color returns for a few weeks!
Denver's monthly mean temperature for September is 63.4 degrees (1981-2010 average) and is the city’s fourth warmest month of the year.
September starts with a normal high of 84 degrees and ends with a normal high of 72 degrees. For low temperatures, the month begins with a normal of 54 degrees and finishes with a normal of 42.
It can still get hot in September, too. Back in 2020, we had a 101-degree day on Sept. 5 — the only triple-digit day we’ve ever had in September. The coldest was 17 degrees on Sept. 29, 1985.
Let it snow?
September is the first month of the snow season in Denver. The earliest snow ever for Denver was on Sept. 3, 1961 when four inches of snow fell that day. We had over four inches of snow
Snow can happen generally late in the month, but we can get some big storms. Pro tip: You can measure the storm, and learn what thousands of weather watchers have reported as far as precipitation, by becoming a CoCoRaHs volunteer.
These are the top seven snowiest Septembers:
- 1971: 17.2 inches
- 1936: 16.5 inches
- 1959: 12.9 inches
- 1895: 11.4 inches
- 1985: 8.7 inches
- 1995: 7.4 inches
- 1908: 6.5 inches
We can still get thunderstorms, but they become more rare as the month goes on. The typical threats are heavy rain and lightning, and not much in the way of tornadoes or large hail.
With about three and a half weeks left of summer, fall foliage will soon attract both residents and visitors to hundreds of beloved places around Colorado.
Denver7's Chief Meteorologist Mike Nelson says it looks like we should see our peak color on schedule this year. The best color over the northern mountains should begin around Sept. 12 and last through the 24th. The central mountains will be about five days behind, with the southern mountain areas rounding out the last days of the month and the first five days of October.