You may have heard that wearing a black shirt will make you hotter than wearing a white shirt or a lighter colored shirt. This is true because the darker the color of a shirt is, the more light and heat it will absorb into the fabric. It will also heat up far faster than a shirt that is a lighter color. This will change the way you feel in a black shirt in many different conditions, depending on how much sunlight you actually get.

If you are indoors and you are not in the sunlight, you will not notice a difference in your temperature. Indoor lighting will not be enough to make you feel hotter in a black T-shirt. If you are indoors and are sitting in a window, you may feel a difference, however. The direct sunlight shining on your black T-shirt will rapidly heat it up and make you feel hotter far faster than you would have felt otherwise. The difference between wearing a black T-shirt and a lighter colored T-shirt will often depend on how hot the sun is and how long you’re sitting in it. If you sit in that window for a few minutes and the sky is overcast, you likely will not notice much of a difference at all. However, if on a hot and sunny day you spend a lot of time in front of this window; you may not be able to tolerate it after just a couple of minutes.

When you are outdoors, the same principle applies. How much hotter you are in a black T-shirt will depend on where you are located, how much sunlight is on you and how long you spend in the sunlight. If you are in the shade, even on a hot day, you will generally not notice much of a difference based on what color shirt is. A black shirt will feel the same as any other colored shirt in this case. Just being in hot weather without being in sunlight will not take a black T-shirt any hotter than any other T-shirt. However, if you venture out of the sunlight, the sunlight will quickly be absorbed by your T-shirt and you will very rapidly fill your shirts start to heat up. If the sky is overcast, this will happen more slowly if at all.

There are a few times when this does not apply, however. If you are on the beach or out on the water, the sunlight may be reflected up from the sand or water and it may heat up your T-shirt just as quickly as if you were out under the direct sunlight. You may have noticed that sitting under an umbrella on the beach does not protect you from sunburn. The same is true if you are out in a boat. The sunlight will reflect off the sand or water just like it would off the surface of a mirror and can result in sunburn and a very hot black T-shirt if you’re wearing one.