Denver experienced the earliest freeze when the temperature dropped so steep quickly, making a similar record going back nearly 150 years.
According to weather reports, Denver's temperature dropped from 93 degrees on Monday to 32 degrees on Tuesday – similar to the one seen on September 8, 1962.
The National Weather Service has recorded six other days since 1872, where the temperature dropped by 60 degrees or more in Denver, but those were during the winter days.
The latest shock came when the city reported a record high of 101 degrees on Saturday, one of its hottest days ever in September.
The current record low is 31 degrees on September 8, 1962.
The record low for September 9 in Denver is 35 degrees from 1898 – another record could be broken Wednesday.
Colorado had snowfall. A powerful surge of cold air from Canada led to the cold front dropped the temperature.
Colorado is no stranger and has experienced strange weather shifts.
The weather is expected to gradually warm-up, with temperatures back up in the 80s by the Denver area's weekend.