Latest numerical weather prediction models from the China Meteorological Administration and ECMWF ensembles converge on a daytime maximum of 26–27°C for Beijing on May 18 under partly cloudy skies with light southerly flow and modest subsidence. This places the market-implied odds near even between those two outcomes while assigning lower probability to 28°C or higher, reflecting the narrow uncertainty range in short-range surface temperature forecasts. May climatology for the capital shows average highs of 26–28°C, and current conditions align with a typical late-spring ridge pattern that limits both strong advection and significant cloud cover. Traders are monitoring the next model runs and any shifts in boundary-layer moisture or wind speed that could nudge the peak by 1°C either way before resolution on the official observation at Beijing’s central station.