As a resident of the Northwest corner of the United States, I can confirm the long-whispered rumor that Seattle citizens secretly knew all along — it doesn't rain that much there. I can't say for sure the motivation behind the rumor behind "rainy Seattle." Some say it's an excellent way to keep the California riffraff away, while others argue it's just standard Northwest behavior, characterized as the Seattle Freeze or Chill. (Another long-held belief that Seattle residents are standoffish to outsiders — outsiders we can distinguish, of course, by our heightened sense of smell that identifies those who haven't eaten salmon in the last two weeks.)
To cut to the chase, Seattle is actually not the rainiest city in the United States; not by a long shot. And let's get one thing straight before moving forward: No one seems to include Alaska and Hawaii on lists of "rainy U.S. cities," which seems grossly unfair. Especially considering that there are places in Hawaii that get Seattle's annual rainfall in just one week [source: Sistek]. Further, some Alaskan towns measure Hawaii-like precipitation, too [source: NCDC].
But most of the data collected is lower-48 centric. And the findings are pretty surprising. The National Climatic Data Center gives the "wettest place" award to good old Mt. Washington, New Hampshire — and with 101.9 inches (258.8 centimeters) of rain per year, it deserves the moniker [source: NCDC]. (It also wins cloudiest, most rain and snow, coldest and windiest. Maybe don't plan your outdoor wedding in Mt. Washington.) In second for most rainfall is Quillyute, in Washington State, with 101.7 inches (258.3 centimeters) of rain per year — 150 miles (241 kilometers) from Washington, and near the famous Forks, where "Twilight" vampires roam [source: NCDC]. Those numbers are based on 30-year averages up until 2008.
Another study that made the rounds in 2007 claimed a rather shocking winner of the "rainiest" crown. WeatherBill studied 195 cities, and looked at 30-year trends for rainfall averages, seasonality and volatility. Based on average annual rainfall, they found that Mobile, Alabama was the rainiest city in the 48 contiguous states. However, one Northwest city got the crown for most rainy days (days with 0.25 inches, or 0.64 centimeters, of rain or more) a year: the capital of Washington State, Olympia, with nearly 64 days of rain annually [source: WeatherBill, Inc.]. Seattle was a measly 41st on the list for cities with most rainfall.
But don't tell the others! Seattle residents are happy to spend their Julys and Augusts basking in the average 25 days a month of sunshine [source: Seattle.gov].
- National Climatic Data Center. "Extremes in U.S. Climate." Jan. 16, 2008. (Dec. 10, 2014) http://www.ncdc.noaa.gov/extremes/extreme-us-climates.php
- National Climatic Data Center. "Normals 1981-2010." 2010. (Dec. 10, 2014) http://www1.ncdc.noaa.gov/pub/data/ccd-data/nrmpcp.txt
- Seattle.gov. "Seattle monthly averages and records." 2014. (Dec. 10, 2014) http://www.seattle.gov/living-in-seattle/environment/weather/averages-and-records
- Sistek, Scott. "Aloha-Oy! Some parts of Hawaii get Seattle's yearly rain in a week." KOMO News. March 14, 2012. Dec. 10, 2014) http://www.komonews.com/weather/blogs/scott/Aloha-Oy-Some-parts-of-Hawaii-get-Seattles-yearly-rain-in-a-week-142678655.html
- Sistek, Scott. "Does it *really* rain in Seattle '24/7'? Not even close!" KOMO News. Dec. 16, 2013. (Dec. 10, 2014) http://www.komonews.com/weather/blogs/scott/Does-it-really-rain-in-Seattle-247-Not-even-close-235815241.html
- Thompson, Andrea. "Study Reveals Top 10 Wettest U.S. Cities." LiveScience. May 18, 2007. (Dec. 10, 2014) http://www.livescience.com/1558-study-reveals-top-10-wettest-cities.html
- WeatherBill, Inc. "Precipitation Averages, Seasonality,Volatility and Trends in the United States." May 17, 2007. (Dec. 10, 2014) http://www.climate.com/assets/LandingPageDocs/rainfallstudy2007.pdf
- WeatherBill.com. "Top 10 Rainiest US Cities and the One Billion Dollar Question." 2014. (Dec. 10, 2014) http://www.climate.com/assets/LandingPageDocs/Top-10-Rainiest-Cities-Summary.pdf