Recent forecast models from sources like the Japan Meteorological Agency and global ensembles point to a high-pressure system building over eastern Japan, promoting clearer skies and light northerly flows that should allow modest daytime warming after late-September rains. This setup favors afternoon highs clustering near 26–28°C in Tokyo on October 1, with limited cloud cover and low precipitation risk supporting the market’s tight distribution between those outcomes. Historical early-October climatology shows typical maxima around 23–25°C, so the current warmer bias reflects the transitional high-pressure influence rather than anomalous heat. Resolution hinges on the precise peak reading from official Tokyo observations, where small shifts in timing or local wind could differentiate 26°C from 28°C. Updated model runs over the next 48 hours will refine the final range.