The Pacific Northwest is house to some of the a lot of breathtaking scenery in the USA, yet that greenery comes at a cost. It rains in the Pacific Northwest, and it rains a lot. Regardless of the gorgeous landscapes and also cosmopolitan cities, the western parts of Washington and also Oregon obtain a negative rap for just how gray and also dismal they have the right to be. But why precisely does it rain so much in the Pacific Northwest?

The reason gloomy weather is so prevalent boils down to prevailing weather fads and also the unique terrain that makes this part of the world so gorgeous. This stretch of land in between Portland, Oregon, and also Seattle, Washington, usually finds itself directly under the track of the jet stream. The jet stream is a fast-moving river of air that encircles the Northern Hemispright here right around the latitude of the U.S.-Canadian border.

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Whenever before the jet stream swoops to the southern, creating a trough, it deserve to geneprice low-press devices at the surchallenge that develop hefty rain and high winds. These troughs and also resulting low-pressure devices often intensify in the Gulf of Alaska and also over the Pacific Ocean off the coastline of Washington, permitting huge storms to crash right into the coastline via ease. Most of these storms are run-of-the-mill rainmakers, lasting for a day or two before relocating on, but some of them have the right to be enormous and reason considerable wind damages and also flooding.

While the photogenic low-press units that swirl right into the shore are the driving force behind the Pacific Northwest’s seemingly endmuch less rains, it’s the region’s terrain that locks in those dismal weather problems. When moist winds blow inland through an approaching storm, the high terrain of the Cascade Range forces the moist air to climb right into the setting, boosting the thick clouds and also steady rainautumn.

Cloudy skies over the Pacific Northwest on May 16, 2017.SSEC/MODIS Today

Even though it rains fairly a bit along the northwestern coastline, actual rainfall totals in the Pacific Northwest differ wildly from area to location due to alters in elevation. Some spots at high elevation right alengthy the shore or along the Cascade Range deserve to check out even more than 10 feet of precipitation in a single year, audit for both rain and also the indistinguishable amount of liquid in snowautumn.

Seattle, Washington, and Portland, Oregon, each just view approximately 36 inches of rain annually, which hardly renders these bustling metro locations the wettest in the country. Compare their rainloss totals to New York City’s Central Park, which measures practically 50 inches of rain annually, and Mobile, Alabama, generally one of the wettest cities in the United States; its proximity to the Gulf of Mexico gives it almost 66 inches of rain yearly.

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The rain that does loss in Seattle and also Portland also, though, falls over a longer duration of time. Between 1981 and also 2010, both cities witnessed a little more than 150 days via measurable precipitation per year, compared to around 122 rainy days in New York City and simply 115 in Mobile. This accounts for the Northwest’s reputation as the gloomiest part of the country—however makes for spectacularly green landscapes once the skies clear out.