Although Wednesday hit the 90s, it may have been one of the last hot days of summer.
Temperatures on Thursday are expected to remain in the 70s, roughly a 20-degree drop from Wednesday.
"(Wednesday was) probably our last really warm day, and could be the end of the 90-degree days for the summer," said Nezette Rydell, meteorologist in charge at the National Weather Service in Boulder.
Boulder's official high Wednesday was 93, which fell just short of the record of 94 set in 1960 and matched again last year.
It was also one of just 22 90-degree days in 2014 in Boulder, with five in August, 12 in July and four in June.
That number is not likely to increase this year, as Rydell said a cold front will move into the area and temperatures will not reach above the 70s. Overnight lows this week could also be in the 40s.
"We're looking at a cooling off throughout the week," Rydell said. "Maybe we will get some warming over the weekend, but we are talking about maybe reaching 80.
"It's going to be a beautiful September week."
Rydell said it's still possible Boulder could see a repeat of Wednesday's weather later in the month.
"It's a little hard to tell at this point; we are still in early September," Rydell said. "This time last September, we were setting records every day."
At the University of Colorado's Farrand Field, some CU students had set up a slackline and a hammock to make the most of the sunny skies and high temperatures Wednesday before they were gone.
"It makes me so sad that it's going to cool down," said sophomore Sam Sweet.
Sophomore Evan O'Leary said he would probably have to make some wardrobe changes as the weather begins to turn.
"We'll have to start wearing extra clothes," O'Leary said.
Added freshman Hannah Wilmes: "Now, I don't have to wear any clothes."
In addition to the cooler temperatures, there is also a 10 to 20 percent chance of showers and thunderstorms after 4 p.m. Thursday. The overnight low is expected to be near 47.
Friday's forecast calls for partly sunny skies with a high of 69 and a 30 percent chance of thunderstorms after noon.
Saturday's forecast calls for partly sunny skies with a high of 72 and a 30 percent chance of showers and thunderstorms after noon.
Camera staff reporter Alex Burness and Samuel Klomhaus contributed to this report.
Contact Camera Staff Writer Mitchell Byars at 303-473-1329 or firstname.lastname@example.org.