London Snowfall Totals & Accumulation Averages
This page pulls together information on when, how much and how often London, Ontario has snow.
There are data and descriptions here of how many days it snows and the total amount of snowfall that London usually gets. There are also monthly and yearly counts of the days that London normally has heavy snowstorms and deep snow accumulated on the ground. Plus there's information on when the city can expect its first and last snowfalls of the season.
All the numbers are long-term historical averages based on weather data gathered from 1981 to 2010 at the London International Airport.
How Often it Snows in London
This first table lists monthly and yearly totals for amount of snow and how many days it snows at least 0.2 centimetres (0.08 inches).
When London Has Its First & Last Snowfalls
The first snowfall of winter for London usually arrives in November, but can show up as early as October.
The season's last snowfall typically happens in April. In some years a late skiff or even a few centimetres of snow lands in May, and quickly melts.
London is normally free of snow every year from June to September.
How Many Snowstorms London Gets
Most days of snowfall in London leave less than five centimetres (2 inches), of fresh snow on the ground. For 13 days a year on average, the amount of new snow totals at least five cm.
Big snowstorms of over ten cm a day normally occur about four times a year. But major blizzards that dump 25 cm or more in one day are rare events that happen only once a decade.
How Much Snow Normally Accumulates in London
For about 84 days a year, London has at least a centimetre of snow on the ground. In mid-winter the snowpack averages around 11 cm deep.
Generally the snow cover begins to build in late December and accumulates further during January.
By the end of March the snow has mainly melted. April rarely has snow deeper than 5 cm.
Environment Canada. Meteorological Service of Canada. Canadian Climate Normals. 1981-2010 Climate Normals & Averages.
Environment Canada. National Climate Data and Information Archive. Canadian Climate Normals or Averages 1971-2000.