The Japan Meteorological Agency's latest forecast, issued early on April 30, pins Tokyo's minimum temperature at 12°C, driving trader consensus to a 100% implied probability on this outcome amid cloudy skies and scattered showers limiting nocturnal radiative cooling. High-pressure weakening over the Kanto region has ushered in cooler, moist air masses, aligning with ensemble model consensus from recent runs showing lows clustered around 12°C—consistent with late-April climatology where overnight minima average 11–13°C at central Tokyo stations. While urban heat islands and precise observation timing introduce minor uncertainty (±1°C), scenarios challenging this include unexpected clearing overnight for deeper cooling or a sudden warm front advection, though current satellite imagery and soundings indicate low likelihood before resolution.