Official Central Weather Administration forecasts project a daily maximum of 28–29°C in Taipei on May 17 under mostly cloudy skies and elevated humidity from the early Meiyu frontal system. Persistent cloud cover suppresses solar heating and convective development, keeping surface temperatures near seasonal norms rather than allowing typical mid-May peaks near 30°C. Ensemble guidance shows limited model spread, with any temporary breaks in overcast conditions or stronger southerly flow potentially elevating readings to 30–31°C. These atmospheric factors explain the tight clustering of market-implied odds across the 29–31°C outcomes, as traders weigh the balance between stable moist flow and modest daytime warming potential before resolution by Taipei Songshan Airport observations.