Persistent northeasterly flow and extensive cloud cover are keeping daytime heating limited ahead of September 21, with official National Weather Service guidance and ensemble models showing a probable daily maximum in the mid-60s Fahrenheit under mostly cloudy skies and a 20–30% chance of light showers. Cooler air advection off Lake Michigan, combined with 15–20 mph northeast winds and high humidity, suppresses the usual seasonal climb toward the late-September average high near 74 °F. Recent model runs cluster tightly between 62–65 °F, producing the near-even market split between the 62–63 °F and 64–65 °F bins; any late clearing or reduced wind speeds could nudge the peak slightly higher, while sustained overcast would favor the lower outcome. Updated NWS forecasts and afternoon model guidance expected in the next 24–48 hours will refine the exact maximum.