London weather in September
Long-run climate averages for London, Ontario in September, plus what the forecast models say for the days ahead.
In September, London averages 23°C by day and 14°C at night. The wettest month is usually August.
September in London averages a daytime high of 23°C and an overnight low of 14°C, which reads as warm for this part of the world. Across the whole year London sees roughly 1008 mm of precipitation.
Climate averages tell you what to pack. They do not tell you what next Tuesday looks like — for that, see the live London forecast with every model compared and how much they currently agree.
London weather by month
what to expect in London through the yearHere is London's typical weather in each month: the average daytime high and overnight low in °C, how each month feels, and the wettest month marked. Use it to plan any trip to London by season.