Weather in London in September
How warm is it in London in September?
In September the typical daytime high in London is 22.5 °C on average, from 25.0 °C at the start to 19.5 °C at the end of the month.
That is 3.9 °C cooler than in August and 7.0 °C warmer than in October.
The last 10 years were 1.1 °C warmer than more than 40 years ago.
Click a day for more: afternoon and night, the usual range, records and how fast it is warming.
The average of the weather stations Toronto (167 km) and Bowling Green Wwtp (265 km); nearer ones count more.