Personally, I think the Flagstaff Airport data is probably tainted by the continuous development over time. The runway was recently lengthed. Additional buildings are constantly going into the area. More parking was added in the late 90s or early 2000’s. All of it can change the heat signal. None the less, here is an interesting graphic from the National Weather Service at Flagstaff. If you dig deeper into what happened over the summer, the story may have been vastly different for you.
Many locations had a much shorter season because of two cold spells. First, June 12 was chilly. The airport reported 33 degrees. A Wunderground reporting station, KAZFLAGS22, reported a low of 31.1 degrees. The Grand Canyon reported 32 degrees. Fort Valley reported a low of 27 degrees. This goes to show what the local variability can do.
Second August 8 was a shocker. The airport reported a low of 35 degrees. Many people reported losing some of their gardens on this day. Granted, KAZFLAGS22 reported a low of 34.9 degrees. The Grand Canyon slipped below freezing on August 8. Again, Fort Valley reported a low of about 27 degrees
So, if you don’t live at the airport, your growing season may have been from June 12 to August 8. A mere 57 days and a potential record breaker in the opposite direction. Many efforts are underway to document the effects of local environmental change on temperature records, such as surfacestations.org. I hope you had the long growing season, it was a beautiful summer