Thermograph

How unusual is the weather? Graded against ~45 years of local climate history.

Weather in London, Ontario, Canada in September

In an average September, London sees a daily high around 23°C and a low around 12°C, based on 1981–2026 of local climate records.

Average high23°C
Typical high range18°C to 28°C
Average low12°C
Typical low range7°C to 17°C
Average daily precipitation3 mm

September records

The most extreme September on record for each metric, across 1981–2026. For rainfall, the wettest and driest are by total September accumulation.

High

Highest 35°C 2002-09-08
Lowest 10°C 1990-09-23

Low

Highest 23°C 2016-09-07
Lowest -1°C 1993-09-30

Feels-like

Highest 49°C 2011-09-02
Lowest -5°C 1993-09-30

Humidity

Highest 20.3 g/m³ 1985-09-07
Lowest 4.6 g/m³ 1993-09-30

Wind

Highest 52 km/h 2010-09-24
Lowest 8 km/h 1996-09-01

Precip

Wettest 190 mm 1986
Driest 20 mm 2023

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