Central Canadian Shield forests
This ecoregion consists of rolling hills, lakes, bogs and rocky outcrops covering a large curved swathe on the Canadian Shield from eastern Manitoba and Northern Ontario running southeastwards through Thunder Bay District to the north shore of Lake Superior and then northeastwards into western Quebec. The area has a cool climate with summer temperatures averaging around 13°C dropping to a very cold -17°C in winter, with the hills around Lac Seul in northwestern Ontario being warmer and wetter than most of the area. Average rainfall in the eastern side of the ecoregion is 550mm per year, rising to 750mm in the centre (near Lake Nipigon for example), up to 900mm in the west. Specific areas include Lake Nipigon and Big Trout Lake (Ontario). These forest contrast with more severe boreal forest ecoregions such as the Eastern Canadian Shield taiga to the north, which covers most of Northern Quebec and Labrador.
Geography of Ontario
Köppen climate classification Dfa is represented in the southwestern tip of Ontario including the city of Windsor. Dfb climate classification is present in London and the southern/western section of the Golden Horseshoe region including Hamilton, Niagara, Oakville and the city of Toronto, have a moderate humid continental climate, similar to the lower Great Lakes portion of the Midwestern United States. The region has warm, humid summers and cold, usually moist winters. Extreme heat and cold usually occur for short periods. It is considered a temperate climate when compared with the remainder of continental Canada. In the fall and winter, temperatures are moderated by the delayed cooling of the Great Lakes; this effect is reversed in spring and summer when afternoon warming is tempered. The lakes' moderating effects allow for a longer growing season than areas at similar latitudes in the continent's interior; some areas exceed 200 frost-free days and have an annual mean temperature of 10 °C (50 °F). Both spring and fall generally consist of mild days and cool nights but are prone to drastic temperature changes over a short timespan. Annual precipitation ranges from 75 to 110 cm (30–43 in) and is well distributed throughout the year with a usual summer peak. Upland areas in this region have cooler conditions, generally more precipitation (especially snowfall), putting them into the Dfb climate scheme. Most of this region lies in the lee of the Great Lakes, making for abundant snow in some areas (London, Goderich for example) over 2 m (80"), while some other areas are not in the direct snowbelt and receive closer to an average of 1 m (40") of snow per year.