Heatwave Hack: How the 'Caveman Method' and Your Phone Can Keep You Cool
The next days will be alarmingly hot in the Northern Hemisphere. In the U.S., temperatures are expected to hit a dangerous range between 39.4 °C and 51.6 °C. Across Europe, the heatwave could push the mercury up to 46 °C in some regions.
And although I could recommend the best AC unit on the market, let’s be real: if you don’t already have one, it won’t help you now. What will help are quick, science-backed strategies you can implement today—with tools you probably already have in your pocket.
While some of these tips might sound like common sense, others genuinely surprised me while researching this piece. At the core of it all, one thing became clear: dealing with a heatwave is about helping your body regulate temperature. So here’s how to stay cool, hydrated, and sane—even when the asphalt feels like lava.
1. Turn Hydration Into a Daily Mission
Your body’s main cooling system is sweat—but it only works if you’re properly hydrated. The problem? Most of us forget to drink water consistently throughout the day.
So here’s my suggestion: Download an app like Waterllama on your iPhone. It turns hydration into a fun challenge with cute animations, smart reminders, and goals like “No Soda Day.” But above all, its most valuable feature is helping you understand your actual fluid intake.
For example, 330 ml of water hydrates you 100%, but 250 ml of coffee only counts as 60%. Simple, right? But this kind of insight can be surprisingly effective—especially when you realize how some drinks, like that cold beer at the end of the day, actually dehydrate you. In fact, one beer might subtract up to 40% from your hydration levels.
Waterllama is free to download, but many of its best features require a subscription, which comes with a 7-day free trial.
Unfortunately, Waterllama isn’t available on Android. After testing several options on the Google Play Store, the app I’d recommend to download is Hydro Coach. It’s a paid app, but at just $2.99 per month, I think it’s worth trying.
While Hydro Coach doesn’t offer the same educational insights as Waterllama, it does provide helpful statistics, personalized drink goals based on your weight, lifestyle, and even the current weather—which can make a big difference during a heatwave.
Bonus tip: If you wear a smartwatch like the Apple Watch or Galaxy Watch, you can log your water intake directly from your wrist—and even set reminders using a third-party app like Waterllama and Hydro Coach. No excuses.
2. Outsmart the Sun with Real-Time Weather Apps
Avoiding the heat is a lot easier when you actually know when and where it’s going to hit hardest. And while I’m a big fan of Apple’s native Weather app, I always keep a backup—just in case.
One of the best I’ve found is Tomorrow.io Weather Forecast (available on both Android and iOS). It delivers hyper-local, minute-by-minute forecasts powered by AI and proprietary data, making it feel way more advanced than your typical weather app.
What makes Tomorrow.io stand out is how actionable it is. You’ll get real-time alerts for things like heat spikes, rain, or poor air quality, along with smart recommendations tailored to your activities—whether you’re heading out for a run, planning your commute, or even flying a drone.
Its clean, interactive design includes custom notifications, radar maps, and forecasting that actually considers impact—not just raw numbers. It pulls data from IoT devices, satellites, and radar to give you 14-day forecasts that feel genuinely useful.
Try This: Use Tomorrow.io to check hourly heat forecasts and plan your walks, workouts, or errands during the coolest parts of the day—usually early morning or late evening.
Pro move: Set push alerts for extreme heat warnings so you're never caught off guard.
3. The 'Caveman Method' Still Works
Before there was AC, there was strategy. The “caveman method” is all about trapping cool air and blocking out heat. To be honest, even though I only read about it today on Tom’s Guide, I’ve been practicing what I like to call the “cave people method” for years. Here’s how it works:
- Close windows, blinds, and curtains during the hottest hours (typically 11 a.m.–8 p.m.).
- After sunset, open everything to let cooler air circulate.
- Turn off unnecessary electronics—they generate heat even when idle.
- Sleep in the lowest part of your home (heat rises!).
Think about it like this: caves stay cool because they’re dark, insulated, and sealed off from direct sunlight and hot air. That’s basically the logic behind the caveman method—you’re mimicking a cave to keep your space naturally cooler during the hottest parts of the day. It’s not fancy, but it works.
4. Wear Tech-Approved Clothing
No need to overthink it: loose, lightweight, light-colored clothes reflect heat and help with airflow. But if you want to go one step further, look for moisture-wicking fabrics (like those used in athletic wear).
Pro Tip: Some smart wearables now track skin temperature and sweat loss—like the Whoop MG I recently reviewed. These can help you spot signs of dehydration or overheating before you even feel them.
5. Eat Light, Chill Often
Heavy meals = more internal heat. Your body works harder to digest large portions of fatty or protein-heavy food. Quick wins:
- Stick to cold meals: salads, smoothies, chilled soups.
- Avoid caffeine and alcohol, which both contribute to dehydration.
- Take breaks in shaded, cool spaces—especially if you're active outside.
Try This: Use a food tracking app like MyFitnessPal (iOS/Android) to help you stay on top of lighter, hydrating meals. You can log what you eat, monitor hydration-friendly nutrients, and avoid foods that spike digestion strain—making it easier to fuel your body without overheating.
6. Don’t Forget Sunscreen—Set a Reminder!
Yes, sunscreen protects your skin, but it also prevents sunburn, which raises your core body temperature and makes heat waves even more dangerous.
Use This Trick: Set a recurring reminder on your smartwatch or phone to reapply sunscreen every two hours—you can use the standard alarm app for that. Or try an app like UV Index (Android and iOS), which provides UV warnings and reapplication timers to help you stay protected.
Final Thoughts
You don’t need to spend money on new gadgets or big appliances to survive a heatwave. Sometimes, the smartest solutions come from a mix of simple tech tricks and old-school wisdom.
So hydrate like it’s your job, block out the sun like a cave person, and use your phone for more than doomscrolling—it might actually help you stay cool.
