London, Ontario Temperatures: Averages by Month
The numbers here tell you how hot and cold the weather usually is in London, Ontario during each month of the year.
The average high and low temperatures are listed below monthly and annually for the city, in both degrees Fahrenheit and Celsius.
Maximums and minimums are only part of the temperature picture. To fill in the rest, there's information on how many days a month get above or below a given temperature.
To find out how often it rises over 10, 20 or 30 °C each month in London, scroll down farther. There are also monthly and yearly counts of days with frost and cold weather.
The first set of high and low temperatures are averages for 2010 to 2019. Everything else here is based on 1981 to 2010 weather.
High °F | Low °F | High °C | Low °C | |
---|---|---|---|---|
29 | 15 | January | -2 | -9 |
31 | 15 | February | -1 | -9 |
41 | 24 | March | 5 | -4 |
54 | 34 | April | 12 | 1 |
69 | 48 | May | 20 | 9 |
76 | 56 | June | 24 | 13 |
81 | 60 | July | 27 | 16 |
79 | 59 | August | 26 | 15 |
72 | 52 | September | 22 | 11 |
59 | 42 | October | 15 | 6 |
45 | 31 | November | 7 | -1 |
35 | 24 | December | 2 | -5 |
56 | 38 | Year | 13 | 3 |
High °F | Low °F | High °C | Low °C | |
---|---|---|---|---|
29 | 15 | January | -2 | -9 |
31 | 17 | February | 0 | -9 |
40 | 24 | March | 4 | -5 |
54 | 35 | April | 12 | 2 |
66 | 45 | May | 19 | 7 |
75 | 55 | June | 24 | 13 |
80 | 59 | July | 26 | 15 |
78 | 57 | August | 25 | 14 |
70 | 50 | September | 21 | 10 |
57 | 40 | October | 14 | 4 |
45 | 31 | November | 7 | 0 |
34 | 21 | December | 1 | -6 |
55 | 37 | Year | 13 | 3 |
Days of Hot Weather in London
London usually has ten days a year with temperatures in the 30s Celsius. Just once every two or three years, a day heats up above 35 degrees Celsius (95 °F). The 30-degree weather can show up here anytime from June to September, and very rarely as early as May.
10 °C 50 °F |
20 °C 68 °F |
30 °C 86 °F | |
---|---|---|---|
January | 1 | 0 | 0 |
February | 1 | 0 | 0 |
March | 6 | 1 | 0 |
April | 19 | 3 | 0 |
May | 29 | 13 | 0 |
June | 30 | 25 | 2 |
July | 31 | 30 | 5 |
August | 31 | 29 | 2 |
September | 30 | 18 | 1 |
October | 24 | 4 | 0 |
November | 9 | 0 | 0 |
December | 2 | 0 | 0 |
Year | 212 | 122 | 10 |
When London Has Frosty Weather
London typically has 142 days a year when the minimum temperature is at 0 °C or below. The average date for the last frost in spring is April 30. Frost normally returns here on October 12. The frost-free period extends for 164 days on average between the final spring frost and the first fall frost.
0 °C 32 °F | |
---|---|
January | 29 |
February | 26 |
March | 25 |
April | 12 |
May | 1 |
June | 0 |
July | 0 |
August | 0 |
September | 0 |
October | 5 |
November | 17 |
December | 27 |
Year | 142 |
How Often London Has Cold Temperatures
London's chilliest winter nights have lows in the minus-twenties °C (below -3 °F). The city averages just four nights a year, usually in January and February, when the thermometer drops that low. Temperatures down to -30 °C (-22 °F) are not normal here.
From November to April, it can remain below freezing all day long. London typically has 57 frosty days a year.
-2 °C 28 °F |
-10 °C 14 °F |
-20 °C -4 °F | |
---|---|---|---|
January | 26 | 13 | 2 |
February | 23 | 11 | 1 |
March | 20 | 5 | 0 |
April | 6 | 0 | 0 |
May | 0 | 0 | 0 |
June | 0 | 0 | 0 |
July | 0 | 0 | 0 |
August | 0 | 0 | 0 |
September | 0 | 0 | 0 |
October | 1 | 0 | 0 |
November | 10 | 1 | 0 |
December | 22 | 8 | 0 |
Year | 109 | 39 | 4 |
References
Environment Canada. Meteorological Service of Canada. Canadian Climate Normals. 1981-2010 Climate Normals & Averages.
Jay Lawrimore, Ron Ray, Scott Applequist, Bryant Korzeniewski, Matthew Menne. 2016. Global Summary of the Month and Year, Version 1.0. NOAA National Centers for Environmental Information.