June - September
Mid-June through September brings Seattle’s best weather—dry and warm, with average temperatures of 70 to 80 degrees, and an occasional stretch of 90-degree weather. It’s also cruise season, with more than 100 ships sailing between Seattle and Alaska every summer. If your Seattle visit will include the state’s natural attractions, summer season is definitely best, but expect crowding. To score a choice hotel room during this season, book four to six months in advance. Pack shorts and sandals, but also long pants and a light jacket—handy in case of a sprinkle or when strolling the windy deck of a ferry.
November - April
Seattle’s urban attractions offer great enjoyment November through April, and in mid-winter astounding travel bargains are available, with some hotel rooms available for half their summertime price. All of the city’s most popular visitor activities are available year-round, although you can expect rainy weather. Seattle’s reputation as a rainy place belies the fact that average annual precipitation is about 37 inches—less than Houston and New York. Rain here comes in the form of frequent drizzle, rather than occasional downpour. The city occasionally experiences a few inches of snowfall, and even this small amount can close the city’s hilly streets.
May and October
To avoid crowds and high prices while still hitting relatively good weather, come to Seattle in May or October. It’s common to have a stretch of mild, sunny days in May, and everything is in bloom. (Rains typically resume in June.) The first half of October often brings Indian summer. There are more locals than out-of-towners on the streets during shoulder season, and hotel rates are moderate. Since the weather is unstable, it’s still wise to pack raingear and warm clothing, along with garments for 60-degree days.