Very high humidity is expected to accompany the heat, especially in the Midwest, and that moisture -- combined with the high temperatures -- will create what's known as a "heat dome" over most of the country. Only the Northwest will be spared.
Those conditions could be deadly. Forecasters say the heat index, which measures what the temperature really feels like when you add in the humidity -- the summer equivalent of the winter wind chill -- will likely reach the dangerous category, increasing the risks of heat exhaustion, heat stroke, and death.
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- Drink plenty of water. Avoid drinks with alcohol or caffeine, which will only dehydrate you faster.
- Eat light meals. Avoid heavy meals that are high in protein, which cause the body to work harder to digest. Eat more carbohydrates so your body doesn't have to use as much energy to digest.
- Wear light-colored clothing, which will reflect sunlight instead of absorbing it. It could keep your body temperature down several degrees.
- Studies show the best clothes to wear while exercising are none at all! This is because air needs to flow over your skin in order for sweat to cool you off -- as much of it as possible. But if that's not an option, loose-fitting clothing is your next best bet.
- Find an air conditioned place to get out of the heat. In temperatures above 80 degrees, fans won't do you any good -- they just blow more hot air around.