Chicago Expects Frost Before 70-Degree Warmup

Chicago’s summerlike mid-October warmth gave way to a sharp cold front, bringing gusty winds, showers and temperatures falling into the 30s. Forecasters warned of widespread frost and possible freezes in colder outlying areas, while lake-effect rain could linger near northwest Indiana; the weekend was expected to turn sunny, with highs in the 50s Saturday and low-to-mid 60s Sunday. Temperatures are then forecast to climb into the upper 60s and low 70s next week under mostly sunny skies. The brief record-setting warmth drew residents to the lakefront, but it also highlighted concerns about increasingly unpredictable extreme weather.