Recent forecasts from regional models indicate a minimum temperature near 21–23°C for Shanghai on June 22, driving the tight clustering of market-implied probabilities around those outcomes. Persistent plum rain (meiyu) conditions associated with the East Asian monsoon maintain extensive cloud cover, which reduces nocturnal radiative cooling and elevates overnight lows relative to clearer-sky baselines. Historical June climatology shows average minima of 20–22°C, with current guidance from sources such as timeanddate and AccuWeather aligning closely with this range amid expected rain showers and overcast skies. Traders appear to weigh residual uncertainty in exact timing of any clearing or localized cooling against official Shanghai Meteorological Bureau observations that will determine resolution.