Forecasts from the National Weather Service and other models show Chicago likely reaching a high near 78–82°F on August 28 under mostly sunny skies and light southeast winds, consistent with late-summer climatology around 81°F. Lake Michigan moderation and variable steering patterns create the main uncertainty, with official guidance clustering near 78–80°F while some ensembles allow slight warming to the low-to-mid 80s. Recent model runs have stabilized around these values with minimal precipitation risk, yet small differences in boundary-layer mixing and exact wind direction sustain the balanced market distribution across the central temperature bins. Traders are weighting the consensus range heavily while acknowledging that final verification at official stations like O’Hare could shift within a narrow window depending on the afternoon peak.