Frosty mornings in Byron are scarcer than in 75% of Canadian towns
Peak summer warmth arrives in July, with afternoons near 26.6°C. A year here swings 36°C from midwinter lows to midsummer highs. Summer afternoons here are warmer than in 70% of Canadian towns. Heating does most of its work from October to April, in months below 10°C on average.
Read at London, 17 km north-east: ECCC’s normals for 1991–2020.
A year in Byron at a glance
Each month’s typical high and low, in °C.
What stands out about Byron’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Byron feels like
Typical highs and lows by season and by month, from ECCC’s 1991–2020 normals.
139 frost days and 128 days above 20°C a year
From October to May frost is routine, and in January it comes on almost every night. Some 11 days a year climb past 30°C.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
962 mm of precipitation in a typical year
September brings the most rain and snow; February, the least. About 128 days a year bring 1 mm or more.
Rain and snow by month
Millimetres
Snowfall: about 152 cm in a normal year
From October to April snow is likely; January is the peak, at about 43 cm.
Snowfall by month
Centimetres
Snow on the ground by month
Centimetres at month’s end
London publishes no full year of snowfall, so these figures come from Strathroy-Mullifarry, 26 km away.
Heating a home in Byron
92% of a year’s heating need falls between October and April. Months averaging under 10°C: October to April.
Degree days add up how far each day’s mean temperature falls below 18°C over a year. A house here needs less heating than 79% of Canadian towns.
Living with Byron’s climate
What the normals mean for a garden, a day outside and the depth of winter.
Tender plants are usually safe from around 3 May until frost returns near 16 October: about 165 days.
The comfortable months for a day outside, highs of 17–27°C and nights of 8°C or more: Jun, Jul, Aug and Sep.
Parks & trails →Frostbite weather, a wind chill under −20, turns up on about 18 days a year.
Expect around 55 sticky days a year with the humidex above 30.
Thirty years of averages say little about one bad storm; Byron’s hazards page does.
Flood & hazards →ECCC’s normals location: London
London is a composite: ECCC joins 3 stations’ readings to make its 1991–2020 normals.
| Distance from the town | 17 km north-east |
| Station altitude | 278 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | No |
| Snowfall from | Strathroy-Mullifarry, 26 km |
| Coldest reading, 1991–2020 | −29.1°C |
| Hottest reading, 1991–2020 | 37.0°C |
| Average wind | 14.0 km/h on average, most often from the west |
| Next-nearest location | Strathroy-Mullifarry, 26 km |
How Byron compares
Against the 2,611 Canadian towns and neighbourhoods of 2,500 or more, each read from its own normals location; the dots are the other locations those towns use in Ontario.
Nearby towns’ climate
Nearby places read from a different ECCC location (places on Byron’s own would show the same figures). The one place listed is 15 km from Byron, the nearest with figures.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Byron London | 26.6°C | −9.1°C | 962 mm |
| Oneida 41 15 km · Strathroy-Mullifarry | 27.3°C 0.7°C warmer | −8.5°C 0.6°C milder | 966 mm |
Byron weather by month
Each month’s normals, 1991–2020: high, low, mean, precipitation and snowfall.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −1.6°C | −9.1°C | −5.4°C | 79 mm | 43 cm |
| February | −0.6°C | −9.0°C | −4.8°C | 63 mm | 32 cm |
| March | 4.6°C | −4.5°C | 0.1°C | 67 mm | 20 cm |
| April | 12.2°C | 1.4°C | 6.8°C | 89 mm | 5 cm |
| May | 19.3°C | 7.7°C | 13.5°C | 89 mm | under 1 cm |
| June | 24.4°C | 13.2°C | 18.8°C | 86 mm | 0 cm |
| July | 26.6°C | 15.3°C | 21.0°C | 81 mm | 0 cm |
| August | 25.7°C | 14.4°C | 20.1°C | 67 mm | 0 cm |
| September | 22.1°C | 10.5°C | 16.3°C | 93 mm | 0 cm |
| October | 14.7°C | 5.0°C | 9.9°C | 83 mm | 2 cm |
| November | 7.5°C | −0.3°C | 3.6°C | 88 mm | 13 cm |
| December | 1.4°C | −5.2°C | −2.0°C | 79 mm | 37 cm |
| Year | 13.0°C | 3.3°C | 8.2°C | 962 mm | 152 cm |
Two years in three, February’s average lands within 3.0°C of normal, against the steadier June
March has the widest record range, −25.6°C in 2003 to 27.2°C in 2012; the tick on each bar is the month’s normal.
Where Byron’s numbers come from
Averages over 30 years, not a forecast.
- Normals: ECCC’s 1991–2020 Canadian Climate Normals for London, the nearest location with a full year of temperatures.
- Other locations: ECCC blanks a month that fails its completeness rule, so the precipitation or snowfall here comes from the next location with all twelve months.
- Comparisons: all Canadian places of 2,500 or more except city totals and reserves, each read the same way.
- Not on this page: sunshine, absent from every 1991–2020 location, and an altitude correction, for want of the town’s own elevation.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Byron’s climate
How warm does Byron get in summer?
July is the warmest month, with average highs of 26.6°C.
How cold does Byron get in winter?
The year’s coldest nights belong to January, at about −9.1°C.
How much rain and snow does Byron get?
The year adds up to 962 mm. September is the peak month (93 mm) and February the low one (63 mm).
Are these figures for Byron itself?
Close to it: they are ECCC’s 1991–2020 normals for London, just outside Byron’s boundary.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Byron →
Adapted from Statistics Canada (Census of Population 2021, population estimates 2025, 2021 census boundaries) under the Statistics Canada Open Licence; this does not constitute an endorsement by Statistics Canada. Neighbourhood names in some cities © OpenStreetMap contributors (ODbL).