Recent numerical weather model consensus from the Met Office and ECMWF places London's May 17 maximum temperature most likely between 15°C and 17°C under moderate westerly flow advecting cooler Atlantic air masses combined with variable cloud cover that restricts peak solar heating. This setup aligns closely with the climatological mid-May average of 16–17°C at Heathrow, the probable resolution station, while ensemble spreads highlight modest uncertainty from afternoon cloud breaks or slight shifts in frontal timing that could nudge the high a degree higher or lower. Trader sentiment clusters tightly around these central outcomes because fresh 06Z and 12Z model runs continue to show stable guidance with limited divergence, though any unexpected clearing or strengthening winds could alter surface temperatures before resolution.