London Weather in September
In September, London averages a high of 19°C (66°F) and a low of 10°C (50°F), based on 55 years of historical weather data from HAMPSTEAD.
19°C
Average high
66°F
10°C
Average low
50°F
33°C
Record high
91°F · 2023
-2°C
Record low
29°F · 2009
What to Expect in London in September
Typical September days in London reach 19°C (66°F) during the afternoon and cool to around 10°C (50°F) overnight. On average, measurable rain falls on about 45% of days this month. Over the past 55 years, September temperatures in London have ranged from a record high of 33°C (2023) down to a record low of -2°C (2009).
For a day-by-day look or other months, see the full London weather history.