**Official National Weather Service forecasts from the Peachtree City office consistently project a high near 91°F for Atlanta on August 28, 2026, under partly to mostly sunny skies with a 30% chance of afternoon showers and thunderstorms after 4 p.m.** Light northwest winds around 5 mph, morning patchy fog, and high humidity support this peak before any convective activity potentially causes temperatures to ease into the mid-80s later. This aligns with the market's strongest implied probability on 90-91°F (56.5%), as traders appear to weight the consensus model output and NWS guidance heavily. Secondary chances on 92-93°F (19.6%) and 88-89°F (19.0%) reflect minor uncertainty around exact timing of cloud cover or storm initiation, while lower bins remain sidelined given the absence of stronger high-pressure ridging or clearer conditions that could push readings higher. Afternoon thunderstorm development tied to diurnal heating and moisture represents the primary variable that could modestly suppress or confirm the peak, consistent with typical late-August patterns in the Southeast where instability often limits maximum temperatures. Updated model runs and real-time observations through the day will likely refine resolution as the market approaches settlement based on official station data.