Highest temperature in London on September 7?

What this question means

London on 7 September: 24°C at 54%, 25°C at 31%, 23°C at 11%, 26°C at 5%, with thin tails below.

The reason to look at this one alongside the 9 September question on the same city is that the two are genuinely different. That one peaks at 20°C. This one peaks at 24°C. Four degrees apart, two days apart, in the same place.

That gap is a weather system, visible in the pricing. Where the Singapore questions on this board look nearly identical from one date to the next — because an equatorial climate barely changes — a temperate maritime city can shift substantially within forty-eight hours as fronts move through.

It is a useful illustration of what a forecast actually contains. Two distributions on the same city are not redundant; read together they show a trajectory rather than a state. The crowd is not just saying how warm it will be, but that it is about to get cooler.