Photo: Nelro2 at en.wikipedia · CC BY 3.0Winter nights in Seaforth are milder than in 83% of Canadian towns
On a normal July day the thermometer tops out near 24.4°C. The gap between a January night and a July afternoon is 32°C. Counting rain and snow together, it is wetter than 70% of Canadian towns. About 140 days a year bring 1 mm of precipitation or more.
Borrowed figures: Seaforth has no normals station, so these come from Goderich, 36 km north-west.
A year in Seaforth at a glance
Each month’s typical high and low, in °C.
What stands out about Seaforth’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Seaforth feels like
Each season’s and each month’s usual high and low, 1991–2020.
About 134 frosts and 109 warm days a year
The frost season runs October to May, and January freezes nearly every night. About 4 days a year top 30°C.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
About 1,035 mm of rain and snow a year
The most falls in June, the least in March.
Rain and snow by month
Millimetres
Goderich publishes no full year of precipitation, so these figures come from Mount Forest, 61 km away.
About 152 cm of snow a year
Expect snow from October to April, with about 43 cm in January, the snowiest month.
Snowfall by month
Centimetres
ECCC’s Goderich normals leave snowfall out; the figures here come from Strathroy-Mullifarry, 78 km away.
Heating a home in Seaforth
90% of a year’s heating need falls between October and April. Months averaging under 10°C: November to April.
Behind the figure: the degrees each day’s mean falls under 18°C, summed for the year. By this count, homes here need less heating than 76% of Canadian towns.
Living with Seaforth’s climate
What the normals mean for a garden, a day outside and the depth of winter.
Mild days and mild nights together (17–27°C by day, 8°C or more at night) belong to Jun, Jul, Aug and Sep.
Parks & trails →Winter brings about 17 days with a wind chill below −20.
Humid summer days, the humidex above 30, number about 44 a year.
A normal year has no blizzard, flood or heat wave in it; Seaforth’s hazards page looks at those.
Flood & hazards →ECCC’s normals location: Goderich
ECCC builds the Goderich normals from 2 stations’ records over 1991–2020, joined where one replaced another.
| Distance from the town | 36 km north-west |
| Station altitude | 214 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | No |
| Precipitation from | Mount Forest, 61 km |
| Snowfall from | Strathroy-Mullifarry, 78 km |
| Coldest reading, 1991–2020 | −31.1°C |
| Hottest reading, 1991–2020 | 34.4°C |
| Average wind | 16.8 km/h on average, most often from the south |
| Next-nearest location | Mount Forest, 61 km |
How Seaforth 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
Places around Seaforth whose figures come from another normals location. The nearest places to Seaforth with figures are 19–35 km away.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Seaforth Goderich | 24.4°C | −7.8°C | 1,035 mm |
| Mitchell 19 km · London | 26.6°C 2.2°C warmer | −9.1°C 1.3°C colder | 962 mm |
| Listowel 32 km · Mount Forest | 25.1°C 0.7°C warmer | −10.9°C 3.1°C colder | 1,035 mm |
| Perth East 33 km · Elora | 25.4°C 1.0°C warmer | −10.7°C 2.9°C colder | 851 mm |
| Exeter 35 km · Strathroy-Mullifarry | 27.3°C 2.9°C warmer | −8.5°C 0.7°C colder | 966 mm |
Seaforth 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 | −1.3°C | −7.8°C | −4.6°C | 92 mm | 43 cm |
| February | −0.6°C | −8.0°C | −4.3°C | 73 mm | 32 cm |
| March | 3.8°C | −4.4°C | −0.3°C | 68 mm | 20 cm |
| April | 10.6°C | 1.1°C | 5.9°C | 74 mm | 5 cm |
| May | 17.4°C | 7.1°C | 12.3°C | 98 mm | under 1 cm |
| June | 22.4°C | 12.4°C | 17.4°C | 100 mm | 0 cm |
| July | 24.4°C | 14.8°C | 19.6°C | 98 mm | 0 cm |
| August | 24.0°C | 14.5°C | 19.3°C | 84 mm | 0 cm |
| September | 21.0°C | 11.2°C | 16.1°C | 85 mm | 0 cm |
| October | 14.3°C | 6.0°C | 10.2°C | 81 mm | 2 cm |
| November | 7.3°C | 0.8°C | 4.1°C | 92 mm | 13 cm |
| December | 1.7°C | −3.9°C | −1.1°C | 90 mm | 37 cm |
| Year | 12.1°C | 3.7°C | 7.9°C | 1,035 mm | 152 cm |
February strays furthest from its normal year to year, by 3.0°C; August the least
Over 1991–2020, March saw both −25.5°C (2003) and 25.1°C (2012), the widest span of any month.
Where Seaforth’s numbers come from
Averages over 30 years, not a forecast.
- Normals: the 1991–2020 Canadian Climate Normals at Goderich, the closest ECCC location with twelve months of temperature normals.
- Other locations: where a location publishes no full year of precipitation or snowfall, the nearest one that does supplies it, named beside those figures.
- Comparisons: every place of 2,500+ in Canada but the city hubs and the reserves, each on its nearest ECCC location.
- Not on this page: hours of sunshine, missing from the 1991–2020 normals, and a height correction: the town has no elevation on file.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Seaforth’s climate
How warm does Seaforth get in summer?
In July, the warmest month, the typical high is 24.4°C.
How cold does Seaforth get in winter?
Midwinter means February, when a typical night reaches −8.0°C.
How much rain and snow does Seaforth get?
A normal year brings 1,035 mm, snow included as water: June is wettest at 100 mm, March driest at 68 mm.
Are these figures for Seaforth itself?
They describe Goderich, the nearest normals location, rather than Seaforth itself.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Seaforth →
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).