According to the Centers for Disease Control and Prevention, on average, over 600 people die from complications related to extreme heat each year in the United States - more than tornadoes, hurricanes, flooding, lightning or any other weather event combined.
Heat-related deaths and illnesses are preventable, but it's important to identify the warning signs and to react swiftly and appropriately when they arise.
What's the difference between heat exhaustion and heat stroke?
Heat exhaustion is the precursor to heatstroke and is a direct result of the body overheating.
According to Mayo Clinic, heat exhaustion is identifiable by heavy sweating, rapid pulse, dizziness, fatigue, cool, moist skin with goose bumps when in the heat, muscle cramps, nausea and headache.
These symptoms may develop over time or come on suddenly, especially during or following periods of prolonged exercise.
When heat exhaustion is not addressed, heatstroke can follow.
Heatstroke is the most severe heat-related illness and, without emergency treatment, it can lead to death. It results when your body temperature rises to 104 degrees Fahrenheit or higher.
"This is pretty complicated because a lot of things can happen. The short answer is it certainly can be fatal...," Peter Sananman, MD, assistant professor of emergency medicine at Penn Medicine, said.
At this temperature, your brain, heart, kidneys and muscles can also become damaged, leading to serious complications or death.
In the case of heatstroke, seeking medical attention is an absolute must, Sananman said.
In addition to a high body temperatures, the symptoms of heatstroke include altered mental state or behavior, nausea and vomiting, flushed skin, rapid breathing and racing heart rate.
"Generally with heat exhaustion, a patient is sweating a lot, whereas with heat stroke, they've stopped sweating and are actually dry. It's a good rule of thumb but isn't always true," he said.
If heat exhaustion is suspected, Sananman advises to remove the sufferer from heat and cool them down, if possible.
This can be done by getting out of the sun and removing or loosening tight clothes, misting the body with water or placing ice packs in the armpits and groin.
Additionally, rehydration is key. Consume plenty of water and avoid beverages that contain alcohol, caffeine or high amounts of sugar, he said.
If you or someone else is experiencing heatstroke, seek immediate medical attention.
How can you prevent heat-related illness?
Though it's important to know how to identify heat exhaustion and heatstroke, both are preventable illnesses.
Have situational awareness, Sananman said.
"Recognize your own symptoms and either go to a cool location/rest or ask for help if you have difficulty getting around," he said.
Additionally, understand that the body does acclimatize to heat, but it will take days to do so.
"So if you haven't been in the heat in many weeks or months, just be aware that your body will not handle it as well as it may have in the past when you were acclimatized," he said.
Proactively hydrating will help keep the body at a safe temperature.
"Drink more than what you think you should," Kent Knable, EMS chief at Centre Life Link, said. "Once you start feeling thirsty, you're actually dehydrated. So, you should be drinking to the point where you're not feeling thirsty at all."
Additionally, respond immediately if you start feeling ill.
"If you're starting to feel ill, or are not feeling well, get out of the sun. Get into the shade," Knable said. "Getting the sun off of you and some cool air blowing against you will help lower your temperature."