How Crowded Is Castillo de San Marcos in January?
January is an average month at Castillo de San Marcos National Monument, running about 1.0× the park's average month — roughly 8% of the year's visitors come in January. That puts it between the March peak and the September low. Overall our best-time score rates January as "Fair" for a visit. Typical January weather averages a high near 68°F and a low around 48°F, with about 2.7" of precipitation. You'll get about 10.3 hours of daylight to explore.
Frequently Asked Questions
January is average at Castillo de San Marcos National Monument (about 1.0× the average month). Our best-time score rates it "Fair". The single best month overall is October.
The busiest month is March and the quietest is September. January sits at about 1.0× the park's average, or 8% of annual visitation.
Source: National Park Service Visitor Use Statistics (1979–2025), NOAA NCEI Climate Normals 1991–2020. Updated 2026-06-20.