Why Is the Pacific Northwest So Rainy?

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iStock

The Pacific Northwest is home to some of the most breathtaking scenery in the United States, but that greenery comes at a cost. It rains in the Pacific Northwest, and it rains a lot. Despite the gorgeous landscapes and cosmopolitan cities, the western parts of Washington and Oregon get a bad rap for how gray and dismal they can be. But why exactly does it rain so much in the Pacific Northwest?

The reason gloomy weather is so common boils down to prevailing weather patterns and the unique terrain that makes this part of the world so gorgeous. This stretch of land between Portland, Oregon, and 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 Hemisphere right around the latitude of the U.S.-Canadian border.

Whenever the jet stream swoops to the south, creating a trough, it can generate low-pressure systems at the surface that produce heavy rain and high winds. These troughs and resulting low-pressure systems often intensify in the Gulf of Alaska and over the Pacific Ocean off the coast of Washington, allowing large storms to crash into the coast with ease. Most of these storms are run-of-the-mill rainmakers, lasting for a day or two before moving on, but some of them can be enormous and cause significant wind damage and flooding.

While the photogenic low-pressure systems that swirl into the coast are the driving force behind the Pacific Northwest’s seemingly endless rains, it’s the region’s terrain that locks in those dismal weather conditions. When moist winds blow inland with an approaching storm, the high terrain of the Cascade Range forces the moist air to rise into the atmosphere, enhancing the thick clouds and steady rainfall.

Rain clouds over Pacific Northwest
Cloudy skies over the Pacific Northwest on May 16, 2017.

Even though it rains quite a bit along the northwestern coast, actual rainfall totals in the Pacific Northwest vary wildly from place to place due to changes in elevation. Some spots at high elevation right along the coast or along the Cascade Range can see more than 10 feet of precipitation in a single year, accounting for both rain and the equivalent amount of liquid in snowfall.

Seattle, Washington, and Portland, Oregon, each only see around 36 inches of rain every year, which hardly makes these bustling metro areas the wettest in the country. Compare their rainfall totals to New York City’s Central Park, which measures nearly 50 inches of rain every year, and Mobile, Alabama, commonly one of the wettest cities in the United States; its proximity to the Gulf of Mexico gives it nearly 66 inches of rain every year.

The rain that does fall in Seattle and Portland, though, falls over a longer period of time. Between 1981 and 2010, both cities saw a little more than 150 days with measurable precipitation per year, compared to about 122 rainy days in New York City and just 115 in Mobile. This accounts for the Northwest’s reputation as the gloomiest part of the country—but makes for spectacularly green landscapes when the skies clear out.

How Waffle House Helps Measure the Severity of a Natural Disaster

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iStock

There are a lot of ways the Federal Emergency Management Agency (FEMA) assesses and addresses the severity of a natural disaster. Meteorology can predict movement patterns, wind gusts, and precipitation. Resources are dispatched to areas hit hardest by torrential weather.

But when the agency needs an accurate, ground-level gauge for how a community is coping during a crisis, they turn to Waffle House.

Since 2004, FEMA has utilized what former administrator Craig Fugate called the “Waffle House Index.” Because the casual dining chain is open 24 hours a day, seven days a week, tracking to see if a location is closed or working with limited supplies can help inform the agency as to whether affected areas are ailing or taking steps toward normalcy.

“If a Waffle House is closed because there's a disaster, it's bad,” Fugate told NPR in 2011. “We call it red. If they're open but have a limited menu, that's yellow ... If they're green, we're good, keep going. You haven't found the bad stuff yet.”

For FEMA, the ability to order a plate of smothered and covered hash browns is an important analytic. If a Waffle House is having trouble getting stock, then transportation has been interrupted. If the menu is limited, then it’s possible they have some utilities but not others. If its locations have locked their doors, inclement weather has taken over. The chain’s locations would normally stay open even in severe conditions to help first responders.

The company has opened a Waffle House Storm Center to gather data in anticipation of Hurricane Florence, a Category 2 storm expected to touch down in the Carolinas this week. But not all locations are taking a wait-and-see approach. One Waffle House in Myrtle Beach, South Carolina has already closed due to the looming threat, making it the first red dot on the Index.

[h/t CNN]

See What Hurricane Florence Looks Like From Space

NASA via Getty Images
NASA via Getty Images

As Hurricane Florence continues to creep its way toward the Carolinas, it’s repeatedly being described as both "the storm of the century” and "the storm of a lifetime” for parts of the coastlines of North and South Carolina. While that may sound like hyperbole to some, Alexander Gerst—an astronaut with the European Space Agency—took to Twitter to prove otherwise with a few amazing photos, and issued a warning to “Watch out, America!”

According to the National Weather Service, “Hurricane Florence will be approaching the Carolina shores as the day progresses on Thursday. Although the exact timing, location, and eventual track of Florence isn't known, local impacts will likely begin in the afternoon hours and only worsen with time throughout the evening and overnight period.”

On Tuesday, Wilmington, North Carolina's National Weather Service took the warning even one step further, writing: "This will likely be the storm of a lifetime for portions of the Carolina coast, and that's saying a lot given the impacts we've seen from Hurricanes Diana, Hugo, Fran, Bonnie, Floyd, and Matthew. I can't emphasize enough the potential for unbelievable damage from wind, storm surge, and inland flooding with this storm.”

Gerst’s photos certainly drive that point home.

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