Traders have converged on an 18°C low for Tokyo on June 16 at 100% implied probability, driven by consistent observational data from the Japan Meteorological Agency showing nighttime temperatures stabilizing near this threshold under prevailing high-pressure conditions. June climatology places typical minimums around 18–20°C, and current model guidance from regional forecasts indicates limited diurnal cooling or advection that would push readings lower before the 24-hour period closes. This skin-in-the-game consensus reflects high confidence in the absence of disruptive fronts or urban heat-island variability. A realistic shift would require an unforecasted marine layer or localized wind change, though such developments appear improbable given the latest guidance and proximity to resolution.