These storms rarely affect eastern Canada. Those most likely to affect the Atlantic provinces originate in a broad band from Florida southeast to the Cape Verde Islands during August, September and October. On average, three tropical cyclones per year affect or threaten to affect Atlantic Canada. However, this number can be considerably higher. In 1969, eight tropical cyclones affected the Atlantic provinces.
Tropical cyclones can retain their force as far inland as Ontario.
In a Transport Canada study of tropical storms that affected Ontario over the period 1900 to 1949, it was found that 25 tropical hurricanes had passed over or close to Ontario. Eight of these had produced weather characterized by extremely high winds and excessive precipitation. When Hurricanes Travel Inland Hurricanes moving inland into a region of uniform temperature, i.e., into a homogeneous tropical air mass, do not reach far inland. Hurricanes moving inland into a region with a substantial temperature gradient retain enough energy to move inland for a considerable distance. Most dangerous to inland areas is the hurricane which arrives at the coast following a path almost parallel to a strong cold front which arrives simultaneously.