Does Feb. 12, 2018 approach a record for the earliest last sub-freezing high?

Dear Tom,

While we just experienced a chilly March, and are now experiencing a downright cold April, our last sub-freezing high was back on February 12th. How does that stack up to the average, and does it approach a record for the earliest last sub-freezing high?

Thanks,
Pat Byrne
Hoffman Estates

Dear Pat,

The city’s last subfreezing high this year was 27 degrees logged on February 12 and despite our backwards spring, every day since then has topped the freezing mark. Checking temperature records back to 1871, Chicago climatologist Frank Wachowski informed us that the city’s average date for the last subfreezing high is March 15. If the February 12 date holds, it will be more than a month earlier than the long-term average and the city’s third earliest on record-trailing only February 7, 1976 (28 degrees) and February 10, 1878(30 degrees).