canIswim

Sea temperature and swimming season in Puerto Rico

When the sea is warm enough to swim in 15 coastal cities in Puerto Rico.

CityWarmestColdestSwimming season
San Juan 29.6°C Sep 26.7°C Mar all year
Ponce 29.9°C Sep 27.0°C Feb all year
Arecibo 29.7°C Sep 26.8°C Mar all year
Mayagüez 29.9°C Sep 27.2°C Feb all year
Fajardo 29.7°C Sep 26.8°C Feb all year
Vega Baja 29.7°C Sep 26.8°C Mar all year
Barceloneta 29.7°C Sep 26.8°C Mar all year
Guayama 29.9°C Sep 27.0°C Feb all year
Aguadilla 29.8°C Sep 26.9°C Mar all year
Río Grande 29.7°C Sep 26.8°C Feb all year
Isabel Segunda 29.7°C Sep 26.8°C Feb all year
Guánica 29.9°C Sep 27.1°C Feb all year
Salinas 29.9°C Sep 27.0°C Feb all year
Quebradillas 29.7°C Sep 26.9°C Mar all year
Lajas 29.9°C Sep 27.2°C Feb all year

Season uses 19°C. Why that number, and where the data comes from