Persistent heat and humidity from a strengthening heat dome have driven trader sentiment toward elevated overnight lows for Chicago on September 2, with model consensus from NOAA and other sources pointing to minimum temperatures in the mid-to-upper 70s°F amid southerly flow and high dew points that limit radiative cooling. Recent NWS guidance highlights heat indices near 100°F during the day, with partly cloudy conditions and a 40-50% thunderstorm chance after midnight potentially moderating the low by a few degrees depending on timing and cloud cover. Historical September 2 averages near 64°F underscore the anomaly, while short-term variability in wind shifts or clearer skies could differentiate the tightly matched bins around 76-81°F versus cooler or warmer thresholds. Updated model runs ahead of the date remain the key catalyst for any probability shifts.