Seattle has a Mediterranean climate, classified as Csb in the Köppen system. The warmest month is July with an average high of 25°C, while the coldest month is January with lows dropping to 2°C. The annual temperature range of 23°C reflects moderate seasonal variation.
The driest month is August with only 5 rain days and 34mm of precipitation. For travellers, August through to the following month typically offers the best balance of warm temperatures and dry conditions. Average humidity ranges from 65% to 65% throughout the year.
Best Time to Visit Seattle
Based on temperature and rainfall data, the best months to visit Seattle are August, July, September. These months offer the most comfortable temperatures with relatively low rainfall, ideal for sightseeing and outdoor activities.
In July, Seattle experiences average highs of 25°C (77°F) and lows of 14°C (57°F). Expect around 6 rainy days and 13 hours of sunshine per day, with humidity averaging 65%. The 11°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 10, so sun protection is advisable on clear days.
Seattle typically sees 6 rainy days in July, with total precipitation of around 25mm. This makes July one of the drier months of the year, and a reliable window for outdoor sightseeing and day trips. Rain showers tend to be brief when they do occur. For context, the driest month in Seattle typically sees 4-6 fewer rain days than July.
Pack light layers, a light jacket for evenings, comfortable walking shoes, and sunscreen for Seattle in July. Daytime temperatures of 25°C are pleasant, but the evening drop to 14°C means a jacket is essential if you plan to be out after dark. Rain is infrequent with only 6 wet days, so a light rain layer is optional. Comfortable walking shoes are a priority given the amount of ground most visitors cover.
Yes, July is an excellent time to visit Seattle. With 13 daily sunshine hours and only 6 rainy days, conditions are ideal for sightseeing and outdoor activities. Temperatures averaging 25°C during the day are comfortable for long walks and outdoor dining. This is peak travel season, so booking accommodation in advance and arriving at popular attractions early in the morning helps avoid the busiest periods.
The average high temperature in Seattle in July is 25°C (77°F), and the average low is 14°C (57°F). The mean daily temperature is approximately 20°C (67°F). The day-to-night range of 11°C is moderate, meaning a single light jacket covers most situations. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.
The best month to visit Seattle is generally July. July offers the most sunshine at 13 hours per day and only 6 rainy days. Average temperatures reach 25°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around July gives you the best chance of dry, bright weather.
July is shoulder or low season in Seattle, meaning fewer tourists and generally lower prices than peak months. With 13 sunshine hours and 6 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.
In July, Seattle suits a range of activities thanks to mild temperatures around 25°C. With few rainy days, outdoor activities are highly recommended. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 13 hours of sunshine, parks and waterfront walks are particularly enjoyable.