Temperatures on Monday soared into the 80's during the afternoon hours. In fact, Sterling reached 86°, Rockford hit 84°, and many locations saw 83-85°. Those numbers were not record highs, but they were very close. Add the humidity into the equation, and many would classify Monday afternoon as down-right hot! Dew points reached the middle and even upper 60's, which is considered "humid." Essentially, Monday's air mass would be typical of July or August when considering the temperatures and humidity. We can thank strong southerly winds at 15-30mph for ushering in the heat and humidity. These kinds of temperatures won't be seen again until possibly next year.
At a time this afternoon, Rockford's temperature was warmer than both Atlanta and Jacksonville. Not only that, but our temperatures were only a couple degrees off of what areas such as Phoenix and Miami saw this afternoon! Those are all cities typically associated with much warmer weather than what we see in northern Illinois. In terms of records, we did break one by 7°! It wasn't the record high for October 17th. The record we broke is the warmest overnight low temperature for the date.
We only dropped down to 68° Monday morning, which is 7° higher than the previous warmest low temperature for the date! This morning's low was 6° warmer than our average high temperature for this date! The record high for the date is 87° at the Rockford airport. While we didn't reach that number, we came very close by topping out at 84°. Some locations in the Stateline (Sterling, Rock Falls, Savanna, Amboy) did see 86° or 87° this afternoon. Temperatures won't be anywhere near today's values in the foreseeable future.