How Crowded Is San Juan Island National Historical Park in April?

April runs about 0.8× San Juan Island National Historical Park's average month, which makes it a quiet month here — roughly 7% of the park's yearly visitors come in April.

In a typical April the park sees about 29,000 recreation visits, based on National Park Service monthly counts from 1979 to 2025.

That makes April the 6th-busiest of the park's twelve months, sitting between the July peak (1.8×) and the January low (0.5×).

On our Best Time to Visit score April rates 61/100 ("Good") — the single best-rated month at San Juan Island, balancing crowds against weather and daylight.

Typical April weather, from 1991–2020 NOAA climate normals at the nearest station, averages a daytime high near 57°F and an overnight low around 41°F, with about 1" of precipitation.

That average of about 49°F is cool, so layers and a shorter daylight window matter.

Because June, July and August together draw about 42% of annual visitors, choosing April instead steps outside that summer crush — the single biggest lever on how crowded the park feels.

You'll have about 13.4 hours of daylight in April to explore — between the 8.1-hour midwinter low and the 15.9-hour summer high.

Park-wide, 2025 drew 420,922 recreation visits, up 3.7% from 405,925 in 2024.

Across the past decade overall visitation has risen about 68.5%, so a April visit is likely to feel busier than it did a few years ago.