How Crowded Is San Juan Island in July?
July is a very busy month at San Juan Island National Historical Park, running about 1.8× the park's average month — roughly 15% of the year's visitors come in July. It is in fact the busiest month of the year here, so expect full parking lots, busy trails and booked-out campgrounds. If crowds bother you, January (the quietest month) or the recommended April are easier. Typical July weather averages a high near 72°F and a low around 50°F, with about 0.5" of precipitation. You'll get about 15.5 hours of daylight to explore.
Frequently Asked Questions
July is very busy at San Juan Island National Historical Park (about 1.8× the average month). Our best-time score rates it "Fair". The single best month overall is April.
The busiest month is July and the quietest is January. July sits at about 1.8× the park's average, or 15% of annual visitation.
Source: National Park Service Visitor Use Statistics (1979–2025), NOAA NCEI Climate Normals 1991–2020. Updated 2026-06-20.