What Do You Wear to the Rainforest in Puerto Rico

El Yunque's climate operates on two certainties: heat and water. The forest floor stays between 80 and 85 degrees Fahrenheit throughout the year, while relative humidity rarely drops below 85 percent even during the January-through-April dry season. Rain falls in sudden, drenching bursts that turn packed-earth trails into ankle-deep streams within minutes, then stop just as abruptly, leaving hikers to navigate exposed roots and algae-slicked boulders under a returning sun. Synthetic fabrics and merino wool dry in under an hour when draped across a daypack during breaks, while cotton stays sodden and heavy for the remainder of a hike. Lightweight long sleeves shield forearms from the sharp-edged ti plants and fern fronds that crowd narrow trail sections, and long pants prevent cuts when scrambling over fallen tree limbs—common obstacles after the May-through-November wet season storms. A wide-brim hat blocks both the midday sun on exposed ridges and the dripping canopy after rain passes through the upper elevations. Footwear determines whether the descent from La Mina Falls becomes a controlled hike or a slip-and-recover scramble. Waterproof hiking shoes with deep lugs grip wet limestone and mud better than trail runners, and closed toes protect against submerged roots that jut from puddles at unpredictable angles. Vibram or similar high-traction soles outperform budget treads on the steepest sections of the Mount Britton Tower trail, where erosion has exposed bare rock faces. A lightweight rain jacket compresses into a fist-sized bundle and deploys in seconds when clouds darken over the Luquillo Mountains. Pack an extra dry shirt in a roll-top dry bag or ziplock—changing into fresh fabric after reaching the trailhead prevents the post-hike chill that sets in once sweat cools on damp skin during the drive back to San Juan. Sunscreen, insect repellent, and a headlamp round out the essentials, since trails close at 5:00 PM and the forest canopy blocks twilight earlier than open terrain.