Climatic Regions of the United States, Marine West Coast
The Marine West Coast climate stretches from northern California through the coastal sections of Oregon, Washington, and southern Alaska. Mild winters and summers distinguish this climate, even though inland climates at the same latitude have bitter winters and hot summers.
In the Marine West Coast region, summer temperature averages range from 15° C to 20° C (from 59° F to 68° F), and the coldest months have a temperature range of 4° C to 10° C (40° F to 50° F). These locations receive the prevailing westerly winds, which bring moist air off the Pacific Ocean. The Marine Northwest experiences frequent storms involving cool, moist air masses. Where the coast is mountainous, the moist air from the ocean rises as it climbs over the mountains and releases its moisture; the result is high annual precipitation with extensive cloud development and profuse rainfall. With the exception of a few warm, sunny summer months, the area experiences fog, drizzle, and gray, leaden skies almost daily. The annual total rainfall may be as much as 1,450 mm (57 in), most of which falls during the winter months.
The region has thin podzol soil, which is poor in agricultural productivity because of excess acidity. Farmers must apply lime and heavy fertilizers to make agriculture viable. Agricultural crops include deciduous fruits (apples and pears), berries, grapes, winter wheat, and horticultural items. Because of the mild winters and lush grasses, dairy farming is also an important agricultural activity.
The Marine West Coast is a land of magnificent coniferous forests with huge stands of tall trees, particularly Douglas fir. In California, some giant sequoias, known as redwoods, reach heights of more than 90 m (300 ft).