Glen Cairn gets fewer frosts than 75% of Canadian towns
July afternoons average 26.6°C. Expect the most rain and snow in September and the least in February. Summer afternoons here are warmer than in 70% of Canadian towns. Picnics, hikes and garden evenings come into their own from June to September, with highs of 22–27°C.
1991–2020 normals from ECCC’s London location, 8.9 km north-east.
A year in Glen Cairn at a glance
Each month’s typical high and low, in °C.
What stands out about Glen Cairn’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Glen Cairn feels like
Typical highs and lows by season and by month, from ECCC’s 1991–2020 normals.
Frost on 139 days, 20°C on 128
The frost season runs October to May, and January freezes nearly every night. Heat of 30°C or more comes on about 11 days a year.
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
On about 128 days a year, 1 mm or more falls.
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
Snowfall: Strathroy-Mullifarry, 36 km away (London records no complete year of it).
Heating a home in Glen Cairn
92% of a year’s heating need falls between October and April. Months averaging under 10°C: October to April.
One degree below 18°C for one day makes one heating degree day; the year’s days are added together. A house here needs less heating than 79% of Canadian towns.
Living with Glen Cairn’s climate
The averages read for the garden, the outdoors and the coldest and hottest days.
Seedlings can go out once the average last frost, around 3 May, has passed; autumn’s first, near 16 October, ends a season of about 165 days.
For long days outdoors, Jun, Jul, Aug and Sep bring highs of 17–27°C and lows of 8°C or more.
Parks & trails →Expect around 18 days a year when the wind chill sinks below −20.
About 55 days a year feel above 30 on the humidex.
For the weather that does damage, from ice storms to floods, see Glen Cairn’s hazards page.
Flood & hazards →ECCC’s normals location: London
Behind the 1991–2020 normals for London are 3 stations, which ECCC combines into one record.
| Distance from the town | 8.9 km north-east |
| Station altitude | 278 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | No |
| Snowfall from | Strathroy-Mullifarry, 36 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, 36 km |
How Glen Cairn compares
Placed among 2,611 Canadian towns and neighbourhoods of 2,500+, each on its nearest normals location; each dot is another location used in Ontario.
Nearby towns’ climate
The nearest places on a normals location of their own: those that share Glen Cairn’s would only repeat its figures. Distances here run 22–40 km: that is how far the nearest places with figures are from Glen Cairn.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Glen Cairn London | 26.6°C | −9.1°C | 962 mm |
| Oneida 41 22 km · Strathroy-Mullifarry | 27.3°C 0.7°C warmer | −8.5°C 0.6°C milder | 966 mm |
| South-West Oxford 34 km · Delhi | 27.5°C 0.9°C warmer | −8.9°C about the same | 965 mm |
Glen Cairn weather by month
Month by month, 1991–2020: the usual high, low and mean, the rain and snow, and the 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 |
From −25.6°C to 27.2°C: March’s coldest and warmest days since 1991
From one year to the next, February’s average typically shifts by 3.0°C around its normal of −4.8°C, the widest of any month, while June’s shifts by 1.1°C.
Where Glen Cairn’s numbers come from
Averages over 30 years, not a forecast.
- Normals: 1991–2020 normals for London from ECCC’s climate data site, the nearest location with every month of temperature.
- 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: every Canadian town and neighbourhood of 2,500 or more, each read from its own nearest location; city totals and reserves are left out.
- Not on this page: a sunshine figure (ECCC published none for 1991–2020) and any lapse-rate correction for height, as the town has no elevation here.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Glen Cairn’s climate
How warm does Glen Cairn get in summer?
Of all twelve months, July has the warmest afternoons, about 26.6°C.
How cold does Glen Cairn get in winter?
Deep winter means January, when nights average −9.1°C.
How much rain and snow does Glen Cairn get?
Measured as water, a year brings 962 mm: 93 mm in September, the wettest month, and 63 mm in February, the driest.
Are these figures for Glen Cairn itself?
Nearly: London, the location behind them, sits just beyond Glen Cairn’s boundary.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Glen Cairn →
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).