Short-range ensemble forecasts from Taiwan’s Central Weather Administration center on a daytime maximum near 29°C in Taipei for June 15, with model spreads driven by expected afternoon thundershowers and variable cloud cover that can suppress peaks by 1–2°C relative to seasonal norms. Persistent frontal activity during the transition out of the mei-yu period has produced widespread overcast skies and scattered convection, limiting insolation and surface heating while keeping humidity elevated. Traders assign the highest implied probabilities to the 28–30°C band because small differences in shower timing or intensity can shift the observed high across these thresholds, with lower odds on extremes reflecting the narrow envelope of current guidance. Updated model runs and Central Weather Administration briefings on convection timing remain the key near-term catalysts.