**Forecasts from the Met Office and supporting global models (GFS, ECMWF) indicate a minimum temperature on August 28 centered on 16–17 °C, directly explaining the tight market split (46 % for 16 °C, 37 % for 17 °C).** Overnight into the 28th, temperatures are expected to bottom out near 17 °C under southwesterly flow, with daytime maxima around 22–24 °C and scattered showers possible later. The primary drivers differentiating 16 °C versus 17 °C are nocturnal radiative cooling rates, modulated by cloud cover, wind mixing, and boundary-layer moisture. Clearer intervals allow greater longwave heat loss to space, potentially pushing readings a degree lower; increased cloud or stronger winds (forecast 10–15 mph) would limit the drop by enhancing downward longwave radiation and turbulent mixing. Ensemble spreads show the largest uncertainty in the pre-dawn hours, with minor shifts in frontal timing or shower placement able to tip the recorded low between these two values. Traders are weighting official agency guidance and recent model consensus heavily, while recognizing that short-range forecast skill remains high but not perfect two days out. Upcoming 00Z/12Z model runs and Met Office updates will likely refine the exact threshold before resolution.