Climate
Overall, the Olympic Peninsula has a moderate marine climate with pleasant summers and mild, wet winters. The Olympic Mountains, part of North America's western coast range, rise suddenly from near sea level to ~8000 feet, intercepting Pacific moisture which is dumped as large amounts of rain. The climate grows wetter from east to west on the Olympic Peninsula. Sunny days are likeliest in July and August. Nearby Sequim is actually in the rain-shadow of the Olympics and is known for sunny days and minimal rain.
Summers tend to be fair and warm, with high temperatures between 65 and 75 degrees F. July, August and September are the driest months, with heavier precipitation during the rest of the year.
While winters are mild at lower elevation, with temperatures in the 30's and 40's, snowfall can be heavy in the mountains, with accumulations of up to 10 feet common.
Flora and fauna
Enormous Sitka spruce and Douglas fir, hundreds of feet high, in the Hoh and Queets rain forest valleys on the west side of the park. Thick, furry epiphyte moss and dense, vibrant vegetation give a beautiful, almost "Tolkien-esqe" enviornment in these unique temperate rain forests, which receive fifteen feet of rain per year on average from the nearby Pacific Ocean.
History
Olympic National Monument was established in 1909 and up-graded to the status of national park in 1938. It was further designated as an International Biosphere Reserve in 1976, and evolved into a World Heritage Park in 1981. Currently, nearly 96% the Olympic National Park is incorporated into the Olympic Wilderness.