Trader consensus on Polymarket overwhelmingly favors an 18°C high temperature in Shanghai today, with 99.9% implied probability, driven by real-time meteorological observations from official stations like Shanghai Pudong (ZSPD) and China Meteorological Administration data showing peak readings around 18°C amid persistent light rain and cloud cover. A recent cold frontal passage has brought easterly winds of 10-20 mph, high humidity near 80-90%, and scattered showers, sharply limiting solar insolation and diurnal heating after yesterday's 29°C high—much cooler than April climatological norms of 18-19°C. With the sun now low in late afternoon and temperatures dropping to 16°C, model ensembles from sources like Weather Underground and AccuWeather confirm no realistic path to 19°C or higher barring an improbable sudden clearing, though official end-of-day validation remains pending.