The Continent of North America is quite a big continent. It is very extensive in the North-South direction. Queen Elizabeth Islands in the extreme North are beyond 80 degrees North while the Panama Canal area is less than 10 degrees North of Latitude. This extensiveness has created many distinct climate types wherein the climatic conditions are more or less uniform. I shall discuss each of them one by one.
Very Cold Winters and Cold Summers
The areas falling under this category are the Northern parts of Canada and the State of Alaska. These regions are extremely cold in winter with more than six months below 32 F ( 0 C) . For instance Mould Bay in the North-West Territory of Canada has nine and Point Barrow in US both has eight months below zero. The summers are cold usually less than 41 F ( 5 C) . At point Barrow the hottest month is July with temperature of 40 F ( 4.4 C) at Mould Bay it is also July with a temperature of just 38 F ( 3 C ). The rainfall is very scanty indeed .Point Barrow records a total annual rainfall of just 4.2 in ( 100 mm) and at Mould Bay it is 2.6 in ( 65 mm) . The range i.e., the difference in temperatures between the hottest and coldest month is however enormous. At Point barrow it is 57 F at Mould Bay it is 70 F. Due to high latitudinal position the days are very long in summer and nights very short while it is other way round in winter.
Cold Winters and Cool Summers
This includes a major part of Canada and North Central U.S . These have cold winters with cool summers . The cities in this region usually have 3 to 6 months below zero and in summer the temperature as a rule does not rise above 65 F (18 C). The annual rain is moderate and is maximum in summer.. To take examples, Calgary in Canada has a high temperature in summer of 62 F ( 17 C) and has five months below 32 F ( 0 C) and has a total annual rainfall of 17in. (425 mm ) with a maxima of 3 in.( 75 mm) in July. Duluth , Minnesota in US also has five months below zero Celsius and high of 65 F ( 17 C ) in summer. The total annual rainfall is 26 inches or 650 mm ( showing a maximum in June of 4 in or 100 mm). The annual range of temperature is enormous ; 49 at Calgary and 57 at Duluth.
Cold Winters and Warm Summers
This includes much of the Central United States. As the area is very far off from either the Atlantic or the Pacific Ocean so it exhibits the typical Continental type of climate with warm summers and cold winters with a tendency towards high summer rainfall. Consider for example the climate pattern of Chicago. Although it has a Jan. mean of 24 F (-4.4 C) which is quite cold but has a high of 73 F ( 22 C ) in July -a range of 39 .The total annual rainfall is 40 inches (1000 mm) with a max of 3.5 inch ( 89 mm) . in September. These areas get bitterly cold air from Canada to the north in winter while in summer there remoteness from the sea rises the temperatures.
Cool Winters and Cool Summers
The areas located on the Pacific coastline of Canada and North- West US experience this type of Climate. In winter when almost whole of Canada is under the influence of very cold wind from the north , the warm pacific current coastline of Canada and Northwestern coastline of U.S has quite a comfortable winter temperature. Warm current of Pacific Ocean keeps the temperate equable. The typical example is Vancouver in British Colombia, Canada . Although Vancouver lies at a Latitude of 60 degrees North but it is amazing that it has no freezing month and the coldest month is Jan. having a temperature of 36 F (2 C ) . The summers are also cool with the temperature of 64 F (17 C ) in July. The rainfall is abundant with a winter maxima as opposed to the continental climate described above. The total annual rainfall for Vancouver is 57 inches (1400 mm ) with a maximum of 9 inches (229mm ) in January.
Warm Winters and Cool Summers
The west cost area below 40 North enjoys a climate which is of Mediterranean type. The areas have a beautiful warm and sunny summer and a wet and very mild winter. The cities of San Francisco and Los Angeles in California belong to this group . The region has no extremes of climate. The mean max for the hottest month is 63 F (17 C) at San Francisco and 69 F (21 C ) at Los Angeles. The winter means being 49 F (9 C) and 57 (14 C ) respectively. As typical of Mediterranean climate, winter has appreciable rainfall and summers are warm and very dry indeed. At San Francisco, four months from June to September have less than 0.5 in ( 13 mm ) of rainfall while rainfall of June is practically Nil. On the other hand the average of Jan is 4 in. (100 mm). Similarly at Los Angeles we find six months from May to October with rainfall less than 0.5 inch. Such a small amount of rain fall in summer is not found any where in North America except in desert regions which we shall shortly discuss.
Warm Winters and Warm Summers
This climate zone covers a vast area and includes South East United States , coastal Mexico, the Caribbean, and Latin America right up to Panama. The peculiar feature of these areas is high temperature around 80 F ( 27 C ) throughout the year and heavy rainfall through out the year. There is no winter season but the summers are not as hot as those of deserts of North America and Mexico . The temperatures are uniformly high throughout the year. Miami in Florida for example has the coolest month at 68 F ( 20 C) and the hottest is 82 (28 C ) thus a range of only 14 is there . Compare it with the stations found in the first category above. Total annual rainfall for Miami is 60 in. (1600 mm ) which is quite high. Constant high temperature through out the year with high humidity and rainfall makes the climate monotonous . However since in winter it is a pleasant respite from the cold of the northern states of U.S so it is a popular tourist resort.
Cool Winters and Warm Summers
The cities of New York, Boston , Philadelphia and Pittsburg etc fall under this category. The winters are quite cool; mean for the coldest month for New York and Pittsburg is 31 F (-1 C) . The summer high at both the places is 74 F (23 C ). The peculiar feature of this type of climate is rain throughout the year and especially in the summer months. Sometimes the high humidity of New York after a heavy downpour in summer makes the weather quite unpleasant. The climate differs from the one with warm winter and warm summer in the sense that the former has no cold season while this type has a well-defined cold season with snow but the summers are quite warm. The winters despite being cold are however saved from the intensely cold winds of the interior of Canada due to somewhat moderating influence of the Atlantic ocean, although the influence is not as great as of the Californian coast which enjoys very mild winters.
Mild Winters and Hot Summers
This climatic regions covers the South Western United States, and the heart of Mexico . Nowwhere in the region the summer temperature is less than 90 F (32 C ) and at Death Valley in Arizona temperatures upto 134 F ( 56 C ) have bee recorded. . Indeed these are the hottest places on earth after Sahara. Only Mexico City is spared the ferocity of heat due its high elevation other wise whole region bakes in intense sunlight in summer. The rainfall is also very scanty and uncertain. In whole of the region no where does the rain fall figure for the year rises above 10 inches ( 250 mm ). The population is sparse since it is the most inhospitable climate of all in North America.
This in short is an overview of different climatic regions found in North America . It is not extensive but does give the reader a general idea about different climates found in this part of the world.