Recent official forecasts from the China Meteorological Administration indicate Shenzhen's daily maximum on May 17 will hinge on afternoon solar heating under a weakening subtropical ridge, with model consensus placing the peak between 26°C and 28°C amid scattered cloud cover and moderate southeasterly flow. Diurnal temperature ranges in the Pearl River Delta during mid-May typically span 5–7°C under humid conditions, where increased low-level moisture and possible brief showers can suppress surface warming by 1–2°C compared to clearer climatological baselines of 29–30°C. Traders assign the tightest spreads to 27°C and 26°C because ensemble runs show minimal divergence on wind speed and precipitable water values through the afternoon window, leaving resolution dependent on final hourly station readings from Bao'an.