Official forecasts from the Met Office and supporting models indicate a maximum of 21–22°C today under high pressure, with sunny intervals, light westerly winds, and minimal cloud cover allowing efficient daytime heating above the 17.9°C seasonal average high. These conditions position 21°C as the leading market outcome at 60% implied probability, while the 34% on 20°C reflects residual uncertainty around exact peak timing and any localized cooling from patchy fair-weather cloud. Recent model runs show consistent guidance with limited spread, and current observations tracking toward the upper end of the 20–21°C range. Resolution hinges on the official daily maximum recorded before midnight, with any late-day cooling or measurement variance capable of shifting the final figure between the two leading bins.