It’s not your imagination: Denver really is setting more high-temperature records

Last Friday, the daily high temperature in Denver flirted with a mark not seen so far in 2023: 100 degrees Fahrenheit.

This year could end up being the first since 2015 without a 100-degree day in the state capital. But the 99-degree high Sept. 1 was still a record for the day — and that is anything but an anomaly in recent years.

Inspired by last week’s 99-degree record-breaker, we decided to chart when each of Denver’s 366 daily records for high and low temperatures was set, going back 151 years to when such records began being kept. (366 and not 365 to account for the record readings on leap days.)

As you can see, the record lows are fairly evenly distributed, with a noted lull in the 1920s, ’30s and early ’40s. But record highs are concentrated in more recent years.

Nearly 50% of Denver’s daily record-high temps — 178 of 366 — have been set since 2000. One-third have been set since 2010, and more than 12% — 46 daily record highs — have been set since 2020.

For comparison, about 19% of Denver’s daily record-low temps have been set since 2000, and about 4% have occurred since 2020.

Last week’s record temp toppled a mark that stood for only four years. It was the fourth record-high temperature set so far in 2023, to go with five record-low temperatures.

And, despite what has felt like a pretty mild summer in Denver, the average daily temperature between June and August actually fell right in line with long-term averages, ranking it the 80th-coolest summer in 151 years, according to 9News.

We created the searchable database below so you can look up the record daily high and low in Denver for any day. But note that the figures are only current through today (Sept. 7, 2023). That means, as climate change warms the state and leads to more extreme weather, this database won’t be updated when, inevitably, new record daily temperatures are set.