**Forecast models from the National Weather Service and other sources indicate a cold front will clear Chicago by Friday night, ushering in northwest winds and building high pressure that promotes clear skies and strong radiational cooling overnight into Saturday, October 17.** This setup favors minimum temperatures in the low to mid-40s°F, consistent with recent model runs showing overnight lows near 42°F amid dry air and light winds. Historical October averages for the date hover around 46°F, but the post-frontal environment supports cooler readings. Uncertainty in exact wind speeds, cloud cover timing, or minor forecast adjustments keeps probabilities closely split between sub-32°F and 50°F+ outcomes, with mid-range bins reflecting the narrow expected window around 40–45°F. Updated NWS guidance and model ensembles released in the next 24–48 hours will likely refine the precise minimum.