Dark clothing absorbs more sunlight than pale clothing, which is why summer shirts feel hotter.

The longer version

Pale fabrics reflect most of the sunlight that strikes them, sending the energy back out again. Dark fabrics absorb far more of it and turn that captured energy into heat, which then warms the material and the air next to it. The absorbed energy comes from visible light and from invisible infrared radiation.

Loose weave and airflow matter just as much, since moving air carries warmth away and lets moisture evaporate. Colour mainly affects how much of the sun's energy is taken in rather than how much body heat escapes. In deep shade with no direct sun, the difference between light and dark cloth becomes much smaller.

Where this entry sits

Everyday physics and chemistry hide small wonders in plain sight, from kitchen reactions to the light in the sky. These short facts explain matter, energy, electricity, magnets, sound, and the simple units we use to measure the world. The full list sits on the Science and Physics page, where every entry is listed in order.