Recent forecasts from the National Weather Service and other models indicate Chicago's overnight low on August 27 will likely fall in the mid-to-upper 60s°F, driven by clearing skies after Wednesday's showers, light northeast winds of 5–10 mph, and radiative cooling under mostly clear conditions. Lake Michigan's moderating influence and dew points near 60°F limit further drops, while historical averages near 65°F provide context. The tight clustering of market-implied odds around the 62–67°F bins reflects model consensus on these factors, with minor variations in exact minimums hinging on precise cloud timing, wind shifts, and urban heat island effects that could differentiate outcomes by a degree or two.