Photo: bgilliard from St. Catharines, Canada · CC BY-SA 2.0Afternoon heat in Forest beats that of 91% of Canadian towns
Midwinter brings lows of about −8.5°C. Precipitation peaks in November and eases off in February. By January nights alone, it runs milder than 81% of Canadian towns. Frost comes on about 137 days a year, so leave time to clear the car.
No ECCC station in Forest has 1991–2020 normals; the page reads Strathroy-Mullifarry, 30 km south-east, instead.
A year in Forest at a glance
Each month’s typical high and low, in °C.
What stands out about Forest’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Forest feels like
Typical highs and lows by season and by month, from ECCC’s 1991–2020 normals.
137 frost days and 131 days above 20°C a year
From October to May frost is routine, and in January it comes on almost every night. About 17 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
Rain and melted snow: about 966 mm a year
About 132 days a year bring 1 mm or more.
Rain and snow by month
Millimetres
Rain alone by month
Millimetres
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
Snow on the ground by month
Centimetres at month’s end
Heating a home in Forest
93% of a year’s heating need falls between October and April. Months averaging under 10°C: November to April.
Degree days add up how far each day’s mean temperature falls below 18°C over a year. In heating terms, homes need less heating than 86% of Canadian towns.
Living with Forest’s climate
What the normals mean for a garden, a day outside and the depth of winter.
Seedlings can go out once the average last frost, around 8 May, has passed; autumn’s first, near 11 October, ends a season of about 155 days.
Afternoons of 17–27°C and nights of at least 8°C arrive in May, Jun, Aug and Sep.
Parks & trails →A normal year has no blizzard, flood or heat wave in it; Forest’s hazards page looks at those.
Flood & hazards →ECCC’s normals location: Strathroy-Mullifarry
Behind the 1991–2020 normals for Strathroy-Mullifarry are 2 stations, which ECCC combines into one record.
| Distance from the town | 30 km south-east |
| Station altitude | 229 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | Yes |
| Coldest reading, 1991–2020 | −32.5°C |
| Hottest reading, 1991–2020 | 37.5°C |
| Next-nearest location | Sarnia, 41 km |
How Forest 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
Places around Forest whose figures come from another normals location. Forest has few close neighbours with figures, so the list reaches 12–40 km out.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Forest Strathroy-Mullifarry | 27.3°C | −8.5°C | 966 mm |
| Kettle Point 44 12 km · Sarnia | 26.5°C 0.8°C cooler | −8.2°C about the same | 871 mm |
| Bayfield 36 km · Goderich | 24.4°C 2.9°C cooler | −7.8°C 0.7°C milder | 966 mm |
| Lucan 38 km · London | 26.6°C 0.7°C cooler | −9.1°C 0.6°C colder | 962 mm |
Forest weather by month
Each month’s normals, 1991–2020: high, low, mean, precipitation and snowfall.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −1.5°C | −8.5°C | −5.0°C | 81 mm | 43 cm |
| February | −0.4°C | −8.3°C | −4.4°C | 62 mm | 32 cm |
| March | 5.1°C | −3.8°C | 0.7°C | 66 mm | 20 cm |
| April | 12.7°C | 2.1°C | 7.4°C | 88 mm | 5 cm |
| May | 19.9°C | 8.2°C | 14.1°C | 84 mm | under 1 cm |
| June | 25.0°C | 13.5°C | 19.3°C | 86 mm | 0 cm |
| July | 27.3°C | 15.7°C | 21.5°C | 78 mm | 0 cm |
| August | 26.2°C | 14.8°C | 20.5°C | 81 mm | 0 cm |
| September | 22.8°C | 11.1°C | 17.0°C | 88 mm | 0 cm |
| October | 15.3°C | 5.8°C | 10.6°C | 84 mm | 2 cm |
| November | 7.8°C | 0.4°C | 4.1°C | 90 mm | 13 cm |
| December | 1.5°C | −4.7°C | −1.6°C | 79 mm | 37 cm |
| Year | 13.5°C | 3.9°C | 8.7°C | 966 mm | 152 cm |
From −28.0°C to 27.5°C: March’s coldest and warmest days since 1991
The month to count on least is February: one year in three its average strays more than 3.2°C from −4.4°C. June moves least, typically by 1.2°C.
Where Forest’s numbers come from
Averages over 30 years, not a forecast.
- Normals: the Canadian Climate Normals, 1991–2020, at Strathroy-Mullifarry (the closest location with all twelve months of temperatures).
- Comparisons: a pool of Canadian towns and neighbourhoods of 2,500 or more, read alike; whole cities and reserves stay out of it.
- 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 Forest’s climate
How warm does Forest get in summer?
In July, the warmest month, the typical high is 27.3°C.
How cold does Forest get in winter?
On a normal January night the air drops to −8.5°C, the coldest of the year.
How much rain and snow does Forest get?
Around 966 mm a year in all, from 90 mm in November down to 62 mm in February.
How long does snow stay on the ground?
Roughly 80 days a year start with snow cover of 1 cm or more.
Are these figures for Forest itself?
Not directly: Forest has no ECCC normals of its own, and Strathroy-Mullifarry stands in for it.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Forest →
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).