The Miami-Fort Lauderdale area averages 175 partly cloudy days per year and West Palm Beach, 159. For comparison, Yuma, Ariz., has 242. Spring (Feb-May) saw the highest number of rain shadow days per month, at nearly 8! In order for precipitation to be counted you have to get at least .01 inches on the ground to measure. Winter saw only 1/4 as many dreary days in the shadow vs. Seattle. The tables below pull together figures on the amount of sunshine each of the largest cities in the United States usually has in a year. According to bestplaces.net Seattle averages 152 non rainy days per year. Precipitation is rain, snow, sleet, or hail that falls to the ground. The following is a list of cities by sunshine duration.Sunshine duration is a climatological indicator, measuring duration of sunshine in given period (usually, a day or a year) for a given location on Earth, typically expressed as an averaged value over several years. On average, there are 152 sunny days per year in Seattle. While Seattle may get more rainfall than Tacoma's 37 inches, Olympia—located further to the south—gets 50 inches of annual precipitation. This includes the days when cloud covers up to 30% of the sky during daylight hours.

There are 43 sunny days per year in Sequim, Washington.

Winter (Nov-Jan) saw 5X as many mostly sunny days in the shadow vs. Seattle. This is the same amount of sunny days in Seattle. Seattle gets some kind of precipitation, on average, 155 days per year. On average, there are 144 sunny days per year in Portland. Couldn't find a mention of sunny days on their site. The US average is 205 sunny days.

Comparatively, Seattle only gest 38 inches of rainfall per year, but it rains much more frequently throughout the year.

Apalachicola, the sunniest spot in Florida, sees an average of 128 clear sunny days per year and Miami has 74.

Summer (Jul-Sep) saw rain shadow areas and Seattle with nearly equal mostly sunny days. In the table below, the average number of Sunny Days for a city in Washington is the total days in a year when the sky is mostly clear. The US average is 205 sunny days. Number of Sunny Days. Portland gets some kind of precipitation, on average, 156 days per year. In order for precipitation to be counted you have to get at least .01 inches on the ground to measure. Precipitation is rain, snow, sleet, or hail that falls to the ground. However, it's not the rainiest city in the state of Washington, either.