By Stephanie Stahl

PHILADELPHIA (CBS) — This blast of super hot weather the Philadelphia region is seeing this week can be dangerous to your health. Doctors say people can become quickly dehydrated and not even realize it — and the combination of high temperatures and humidity can be especially dangerous.

Talk about hard work. Imagine being a group of construction workers in Philadelphia welding on this sweltering day. It doesn’t get much more challenging.

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The super-hot blast of weather has the city baking everywhere in what’s called the heat island effect, which is caused by all the concrete that radiates even more heat.

“Unfortunately, we’re starting to see this year after year, it’s getting hotter and hotter, climate change is real,” Sarah O’Sell said.

Doctors say the sizzling heat is potentially dangerous and can cause a wide range of problems from dehydration and heatstroke to an increased risk of heart disease, and even death.

CBS3 spotted some kids cooling off at Love Park with a majestic view of City Hall on Monday, but there’s no majesty with our weather — it’s sweltering and oppressive.

Children and the elderly are most susceptible, but doctors say the heat can be harmful to everyone.

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“Heat is a stress on the body, it’s a stress on the mind,” Dr. Jennifer Vines, county health officer, said. “It is uncomfortable to be hot for long periods of time.”

What makes this sweltering blast especially dangerous is the combination of high temperatures and humidity — the heat index.

High humidity makes it harder for sweat to evaporate, which is what cools the body. Heat exhaustion is the first sign of trouble.

“So you might get nausea, headaches, light-headedness, muscle cramps,” health science expert Dr. June Spector said.

Signs of the more dangerous heat stroke include:

  • pale, red, dry skin
  • confusion
  • dilated pupils

These symptoms need immediate medical attention.

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Doctors say even mild dehydration can impact your cognitive ability and mood. It’s best to stay inside as much as possible and drink plenty of water, even before you feel thirsty.

Stephanie Stahl