Earliest and Latest Days at or Below 0° C in London

This is a list of the earliest and latest days in a winter season where the low temperature fell to at least 0 °C in London, Ontario history. It is based on NOAA data from the years 1883–2024.

Earliest freezing temperature in London?

The earliest in a winter season that London, Ontario has recorded a low temperature of 0 °C or below is September 9 which happened in 1883.

Latest freezing temperature in London?

The latest in a winter season that London, Ontario has recorded a low temperature of 0 °C or below is June 16 which happened in 1908.

Earliest Days ≤ 0 °C

Date	Year	Temperature
September 9	1883	0.0 °C
September 10	1883	-1.7 °C
September 11	1917	0.0 °C
September 14	1911	0.0 °C
September 16	1923	-0.6 °C
September 17	1959	-1.1 °C
September 18	1943	-0.6 °C
September 19	2020	-0.1 °C
September 19	1929	0.0 °C
September 19	1916	-1.7 °C
September 20	1973	0.0 °C
September 20	1929	-2.2 °C
September 21	1973	-2.8 °C
September 21	1927	0.0 °C
September 21	1904	0.0 °C
September 21	1897	-1.1 °C
September 22	1999	-0.2 °C
September 22	1904	-3.3 °C
September 23	1974	-1.1 °C
September 23	1904	0.0 °C
September 23	1896	-2.2 °C

Latest Days ≤ 0 °C

Date	Year	Temperature
June 16	1908	0.0 °C
June 11	1972	-0.6 °C
June 10	1913	0.0 °C
June 9	1913	0.0 °C
June 8	1949	0.0 °C
June 6	1894	-1.1 °C
May 31	1930	0.0 °C
May 29	1936	0.0 °C
May 29	1894	-0.6 °C
May 29	1889	-1.7 °C
May 29	1884	-1.1 °C
May 28	1927	0.0 °C
May 28	1907	0.0 °C
May 28	1902	0.0 °C
May 27	1925	-0.6 °C
May 27	1915	-2.8 °C
May 27	1891	-0.6 °C
May 26	1969	-1.7 °C
May 26	1925	-1.1 °C
May 26	1897	0.0 °C