Mother Nature can be so fickle. While September brings the start of autumn, she was intent on keeping summer rolling along and in doing so, delivered mercury readings well above normal.

The month was a calm one, lacking much of any kind of drama beyond the temperatures. We started out very warm and dry for the first three days then, finally, a little bit of relief arrived. Temperatures cooled a bit and we received a nice shot of rain on the 4^th and 5^th.

• September 2024 in pictures – view the monthly photo slideshow

For the next two weeks, dry conditions dominated with no precipitation. Over the period temperatures remained well above normal.

Finally, on the 21^st, we saw some relief and temperatures on the 21^st and 22^nd were only in the 60s. We also received a welcome shot of rain totaling 0.81 inches.

Temperatures rebounded on the 23^RD and dry weather continued through the end of the month.

In the end, Thornton saw an average temperature for September 2024 of 67.9 degrees. This was far above the running 17-year average for the month of 64.2. In fact, it was Thornton’s warmest September over the period. Temperatures in Thornton ranged from a high of 93.1 degrees on the 3^rd down to a low of 42.7 degrees on the 23^rd.

For Denver, as measured at Denver International Airport, the month was a good bit warmer recording an average of 70.0 degrees. This too was far above the month’s average of 64.8 degrees. Further, it put September 2024 into the books as the Mile High City’s warmest September on record.

Thornton really only saw two rain events but both were pretty decent ones, dropping 1.26 inches into the rain bucket for the month. That was a bit below our September average of 1.48 inches.

Denver recorded very similar numbers with 1.24 inches of precipitation. This was just shy of the Mile High City’s September average of 1.35 inches.

Neither Thornton nor Denver recorded any snow during September 2024.

Click here to view Thornton’s complete September 2024 climate summary report.