Redwood National Park is now managed along with three California state parks as the Redwood National and State Parks, about 132,000 acres of the greater coastal redwood forest. This belt of the loftiest of all trees runs some 500 miles from northern California to extreme southwestern Oregon, and represents the entire natural range of the species. Much of the reason for the trees' size and modern distribution has to do with climate.

General Climate

Redwood country lies within a marine west coast climate zone, a type usually encountered between 40 and 60 degrees latitude on the western ocean shores of continents. Here, subject to prevailing westerly winds, oceans are the dominant climatic factor: Because they warm and cool more slowly than land, oceans moderate temperatures year-round and supply ample moisture on a seasonal basis in the form of rain, fog and cloud cover. Northwestern California's redwood forest is the southerly margin of a North American sprawl of marine west coast climate stretching to southern Alaska, all of it restricted inland by the great Pacific mountain chains. The redwoods lie in a warmer, drier part of a climatic zone that is mostly cool and wet.

Precipitation and Temperature

Most of the redwood forest's precipitation falls during winter, generally due to the jet stream, the high-altitude funnel of fast-moving winds that forms the margin between colder polar air and warmer subtropical air to the south. The jet stream migrates south into the region of the Pacific Northwest during winter, pulling storms off the ocean -- often those originated in the tempestuous Gulf of Alaska. These moist air masses rise over the coastal ranges and release plentiful amounts of rain, some 80 to 140 inches in the redwood forest. Beginning in spring, the jet stream moves northward and dry, high-pressure systems usually prevail in the Northwest. The ocean's moderating influence means the redwood forest typically sees temperatures of between 40 and 60 degrees F throughout the year, according to the National Park Service.

Fog Belt

While rain is usually scarce in summer, the windward slopes of the Pacific Northwest coastal ranges are frequently awash in fog off of the ocean during this season. In fact, the fog belt roughly defines the inland extent of the coast redwoods: They need that crucial moisture during the dry season to survive.


The redwood forest's moderate climate makes it one of the more predictable parks to visit, weather-wise. Summer visitors might not need much rain gear, but should bring sweaters or light jackets for cool temperatures. Between autumn and spring, gear to ward off drizzle and warm clothes to combat winds during Pacific storms are crucial.

Temperate Rainforest

The influence of the Pacific Ocean and rugged coastal topography synchronize to support, in the Pacific Northwest, the largest temperate rain forest in the world. Coast redwoods, of course, are the tallest trees of all, reaching heights of better than 360 feet. Up along the coast and the western slopes of the Cascade Range grow other massive trees, like Douglas fir, western red cedar and Sitka spruce.


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