Previous Climate In Seattle:
Seattle's climate is usually described as oceanic, dry-summer oceanic, or temperate marine, with cool, wet winters and warm, relatively dry summers Temperature extremes are moderated by the adjacent Puget Sound, greater Pacific Ocean, and Lake Washington. The region is largely denied Pacific storms by the Olympic Mountains and Arctic air by the Cascade Range. Despite being on the margin of the rain shadow of the Olympic Mountains, the city has a reputation for frequent rain. This reputation stems from the frequency of precipitation in the fall, winter, and spring. In an average year, at least 0.01 inches of precipitation falls on 150 days, more than Boston, New York, Washington, D.C., or Atlanta. It is cloudy 201 days out of the year and partly cloudy 93 days. The location of official weather and climatic records, the Seattle-Tacoma International Airport, is located about 19 km south of downtown in the city of SeaTac, and records more cloudy days and fewer partly cloudy days per year. For this reason, official weather and climatic records may not accurately reflect the weather and climate conditions of the city proper.

More About Seattle:
At 37.41 inches, the city receives less precipitation annually than Boston, New York, Washington, D.C., Atlanta, and most cities on the Eastern Seaboard of the U.S. Yet, due to local variations in microclimate, Seattle proper receives significantly less precipitation than some other locations west of the Cascades. The suburb of Bremerton, about 15 mi to the southwest of downtown Seattle, receives 54.82 inches of precipitation annually. Statistics show that the city is becoming wetter: the current annual rainfall average of 952 millimeters reflects an increase of 11 mm. Seattle receives the largest amount of rainfall of any U.S. city of more than 250,000 people in November, and is in the top 10 through winter, but is in the lower half of all cities from June to September. Seattle is in the top 5 rainiest U.S. cities by number of precipitations days, and it gets the least amount of annual sunlight of all major cities in the lower-48 states. Thunderstorms are rare, as the city reports thunder on just seven days per year.
Seattle experiences moderate rain and heavy rain during the months of November, December, and January. The city receives roughly half of its annual rainfall (by volume) during these three months. In late fall/early winter, atmospheric rivers, and Pacific storms are common. Light rain & drizzle are the predominant forms of precipitation during the remainder of the year. On occasion, Seattle experiences extraordinary weather events. One such event occurred on December 2–4, 2007, when sustained hurricane-force winds and widespread heavy rainfall associated with a strong "Pineapple Express" event occurred in the greater Puget Sound area and the western parts of Washington and Oregon. Precipitation totals exceeded 13.8 in some areas with winds topping out at 209 km/h along coastal Oregon. It became the second wettest event in Seattle history when a little over 130 mm of rain fell on Seattle in a 24 hour period. The rain contributed to five deaths and widespread flooding and damage.