From July 21 to 25, nearly half of the U.S. population—around 160 million people—are bracing for a brutal midsummer heatwave. What began in the Southeast is now pushing its way into the Mid-South, Midwest, and even the Northeast, bringing not just extreme heat, but an alarming rise in health risks. This isn’t just a stretch of warm weather—it’s a direct consequence of climate change, and it's making heat-related illnesses like exhaustion and stroke increasingly common, and more dangerous.A Climate Central analysis confirms that human-induced climate change has made this extreme weather event at least three times more likely. For those in Arkansas, Kansas, Missouri, Oklahoma, northern Louisiana, and Texas, triple-digit temperatures are expected across multiple days, with humidity pushing heat index values to 110°F in some areas.Even nighttime will offer little relief. In states like Florida, Georgia, and South Carolina, overnight temperatures are expected to hover 15°F above normal, making it harder for the body to cool down—a key factor in heat-related illness.What Happens to Your Body in Extreme Heat?When your body is exposed to prolonged high temperatures—especially when paired with humidity—it struggles to regulate its internal temperature. Sweating is the body’s natural cooling mechanism, but excessive heat can outpace this system, leading to heat exhaustion and, if unchecked, the more severe heat stroke.Heat exhaustion typically shows up as fatigue, dizziness, nausea, headache, and excessive sweating. Dr. Madhumidha K., MBBS, MD, Internal Medicine at Apollo Spectra Hospital, explains,“This could lead to loss of essential salts through sweat, and if not managed, progress to heat stroke. At that point, the body can no longer cool itself, leading to confusion, unconsciousness, and even organ failure.”Heat stroke, unlike exhaustion, is a medical emergency. It can lead to permanent damage or death if not treated quickly. And it’s more common than many think—especially during heatwaves like this one.Who’s Most at Risk?While no one is immune, some groups are far more vulnerable:Young children whose bodies heat up fasterOlder adults who may have underlying conditions or reduced thirst responseOutdoor workers, including construction crews, postal workers, and landscapersPeople with chronic illnesses, especially cardiovascular or neurological diseasesThose without access to air conditioning, particularly in rural or under-resourced areasDr. Madhumidha adds, “We often assume these illnesses strike only outdoors. But they can happen anywhere—even in your own kitchen or garage if the space isn’t properly cooled.”Why the Nighttime Heat Is Especially Concerning?This year’s heatwave isn’t giving our bodies a break even after sunset. Unusually high overnight lows in the mid-70s to low 80s are predicted—dangerously warm for the body to recover. Sleeping in heat-stressed conditions can elevate heart rate, increase dehydration, and disrupt sleep, weakening the body’s natural defenses by morning.Role of Climate ChangeWhat used to be considered "unseasonably warm" is now becoming the norm. According to the Climate Shift Index, this kind of intense heat is now 3x more likely due to climate change. The “heat dome” anchoring this weather pattern traps hot air and drives up humidity, worsening heat retention both day and night.This isn’t isolated. The frequency, intensity, and duration of heatwaves are increasing across the globe—something public health officials are now treating as a climate-linked health crisis.How to Protect Yourself and Family From Heat-Related Illness?Hydration is your frontline defense. Aim to drink water consistently, not just when you’re thirsty. Add water-rich foods like cucumbers, watermelon, or citrus fruits to your diet. Dr. Madhumidha advises, “Avoid drinks that dehydrate you—like caffeinated sodas or alcohol—especially during peak heat hours.”Dress light and breathe easy, choose loose, breathable fabrics like cotton or linen. Dark colors trap more heat, so opt for light tones when stepping outside.Time your outdoor activity, avoid physical exertion between 11 a.m. and 4 p.m., when the sun is at its peak. If unavoidable, take frequent breaks and stay in shaded or air-conditioned areas when possible.Keep your home cool—even on a budget, if air conditioning isn’t an option, use fans strategically. Keep blinds closed during the day, use cold showers to lower your core temperature, and place wet towels on your forehead or neck to cool down quickly.Be proactive for those at higher risk, check on elderly neighbors, keep children hydrated, and ensure pets have shade and cool water. Watch for early warning signs of heat stress—confusion, flushed skin, or excessive fatigue.When to Seek Medical Help?If someone shows signs of heat stroke—hot skin, rapid pulse, disorientation, or fainting—call emergency services immediately. Until help arrives, move them to a cool place, remove excess clothing, and apply ice packs or cool water to their body.As extreme heat events become more common, this isn’t just about staying cool for one weekend. It’s about adapting our infrastructure, homes, work policies, and public health strategies to match the new climate reality.Dr. Madhumidha stresses, “Sweating is good—it helps eliminate toxins. But when the heat overwhelms your system, you need to step in. Prevention isn’t just common sense now—it’s survival.”With climate-linked heatwaves growing more intense and widespread, heat exhaustion and stroke are no longer rare events—they’re foreseeable, preventable threats. Staying informed, acting early, and looking out for others could save lives this week.