To go from summer to winter, you usually have to go through fall first. Or you could live in Denver. The city recorded one of the biggest temperature changes in its history this week, with the mercury going from a balmy 83 degrees Fahrenheit at 3pm Wednesday to a frosty 19 degrees at 9am Thursday, the Denver Post reports. The cold front that moved in Wednesday evening brought the biggest two-day October temperature switch on record in Denver, and Friday morning is expected to have the coldest temperatures recorded so early in the season, CBS Denver reports. Heavy snow caused numerous car crashes Thursday as well as flight delays at Denver International Airport. (More Denver stories.)