Trader sentiment clusters tightly around 16–19°C for Tokyo's March 27 high, reflecting Japan Meteorological Agency forecasts projecting a mild 17°C peak under building high-pressure ridges after recent frontal passages. Ensemble models like ECMWF and GFS diverge by 1–2°C due to jet stream undulations and urban heat island amplification in Tokyo, where concrete retains daytime warmth into evening. Historical March 27 averages hover at 14°C, with variability from 8–23°C tied to early sakura-season instability; current upper-air data shows warming advection favoring the 17°C lead (32.5% implied odds), but traders hedge against evening cloud cover potentially capping at 16°C. Key watch: JMA's evening update could shift probabilities as observations firm up.