San Juan, Puerto Rico – A blistering heat advisory is in effect across Puerto Rico today, with temperatures and humidity expected to create dangerous conditions for residents in low-elevation and urban zones from 10 a.m. to 4 p.m. Thursday.
According to the National Weather Service in San Juan, this short-term but intense advisory spans San Juan, Ponce, Mayagüez, and dozens of surrounding municipalities. The high heat index could lead to heat-related illnesses, particularly for individuals without air conditioning, adequate hydration, or shaded outdoor relief.
Health officials and emergency agencies are urging residents to limit outdoor activity, especially in construction, agriculture, and other heat-sensitive industries. OSHA recommends frequent breaks in cool, shaded environments for those who must work outdoors. Vulnerable populations—including the elderly and young children—are at heightened risk.
In urban centers such as Carolina, Caguas, Bayamón, and Humacao, heat buildup in concrete-heavy areas may intensify discomfort and strain local power and health systems. Residents are urged to stay indoors, hydrate often, and check on neighbors.
The heat advisory ends at 4 p.m., but temperatures remain elevated into the evening. Additional advisories may be issued if conditions persist.
