In really hot weather (like scorching hot), wear loose clothing that covers your whole body. Look at what the locals wear, which tends not to be board shorts and a pump vest, but clothing that is loose and full of air. The idea is to create an insulating layer of air that will have a high moisture content (sweat), which when combined with sweat on your skin, and sweat in the cloth, will transfer heat away from your body. White is good at reflecting the sun, but thicker dark fabrics can feel cooler, white or black a debate that really isn’t important at 50 degrees C! What is important is that you look at the clothing in the same way an Inuit does, adjusting it to adapt to the conditions. As soon as you get any breeze, you’re best to expose more skin if not in direct sun, to allow the heat to evaporate directly. Also, avoid high tech high wicking fabrics as you don’t want dry skin, but to hold the moisture, so cotton works best, with heavy-duty cotton being cooler than very thin cotton (unless it’s windy). Also, cover the head and wear sunglasses (your eyes are covered in a film of moisture and at high temperatures, it’s like holding a hairdryer to your face. Get a shemagh (Arabic scarf), as this can protect your neck and also your face and head when worn in different styles (or just a sweat rag), and can often just be draped over your head sauna style. Sunscreen is really only used on your face and hands and feet (if wearing sandals), or not at all, as you should limit your skin/sun exposure to a minimum.
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