Seattle has many nicknames – from the Emerald City to the Coffee Capital of the World, another popular name for Seattle is the Rain City. You can probably guess why Seattle is known as the Rain City because it frequently rains in the Pacific Northwest. Seattle is known for its wet weather, so let’s look at why it rains so much.
According to the Weather Channel, Seattle endures an average of 152 rainy days a year. A day is classified as rainy when at least 0.01 inches of rain, or melted snow and ice, falls. This amount of rainy days is much less than most other cities in the United States, but it is necessary to note that the amount of rain that falls is not that much. While it does rain frequently in Seattle, it rarely rains heavily. In fact, the Weather Channel reports that Seattle typically sees only five days a year with at least one inch of accumulating precipitation. Due to the low amount of rain, the Rain City only sees on average 37.18 inches of annual rainfall. This is actually lower than much of the Eastern and Southern United States. (Compare it to New York City’s Central Park, which measures approximately 50 inches of rain every year)
Seattle and the rest of the Pacific Northwest have some of the most beautiful scenery in the world. Part of the reason that the area offers such gorgeous terrain is due to the prevailing weather patterns. The Pacific Northwest, particularly the land between Seattle and Portland, usually falls below the track of a jet stream. A jet stream is a quick flowing, fairly narrow air current found in the atmosphere and is responsible for moving the weather systems that affect us.
Whenever jet streams swoop to the south, forming a channel, it can create low-pressure systems at the surface that generate heavy precipitation and powerful winds. These channels and resulting low-pressure systems usually strengthen off the coast of Washington. When the storms strike, most produce average rainfall, but some can cause significant wind damage and flooding. While the low-pressure systems that whirl into the coast are the main force behind Seattle’s frequent rain, it’s the Pacific Northwest’s terrain that locks in those dismal weather conditions. The high ground of the Cascade Mountain Range pushes the moist air to rise into the atmosphere, enhancing the thick clouds and steady rainfall.
While it may often rain in Seattle, the city actually faces less rainfall than other cities in the United States.
Mitch Levy has spent nearly 30 years in radio and sports broadcasting after earning a degree in Broadcast Journalism from Syracuse. Read more of his advice for the radio industry or check out his Twitter!