Avoid storing these items in your car during hot weather

In the right weather, a parked car becomes a little sun trap. The kind you walk into and instantly regret. Sunglasses fog up, your thighs stick to the seat, and for a brief second, you wonder if you might faint from the sheer audacity of heat. What we rarely consider, though, is what’s happening to everything inside that car. Not just our bodies—but our belongings. Our bottles, devices, deodorants, snacks. Things that were never designed to survive a mobile oven on wheels.

But let’s zoom out for a second. Because while this sounds like a safety checklist—and it is—it’s also a small story about culture. About what we carry, what we leave behind, and what we don’t bother to question until it’s melted, exploded, or ruined. This isn’t just about lighters and food. It’s about how we treat our cars like extension cords of our lives, and how the heat calls our bluff.

Let’s begin where most people do: with the sudden bang.

When pressurized cans get too hot, they explode. That’s not metaphor. That’s physics. A car parked under the sun can reach 60°C (140°F) in less than an hour. Inside that heat dome, aerosol cans—like insect repellent, hairspray, dry shampoo, or deodorant—can rupture without warning. It’s not even dramatic. Sometimes they hiss and leak slowly. Other times they burst. The damage isn’t just to your dashboard; it’s to your sense of normal. Because suddenly, that harmless air freshener becomes a fire risk. And your “just five minutes” turns into “how did this happen?”

But the surprise isn’t limited to cans. Cigarette lighters, especially refillable ones, are quietly dangerous when left behind. Even tucked away in the glove compartment, they can combust under heat stress. The irony? We fear fireworks on New Year’s, but we store mini firestarters next to our tissue boxes in July.

Then come the electronics. And here’s where it gets quietly tragic. We treat our phones, tablets, and game consoles like fragile royalty. We buy silicone bumpers, lens protectors, blue-light shields. We wipe them down obsessively. But leave them in the car on a hot afternoon? Poof. Their batteries begin to degrade. Lithium-ion cells expand. Heat sensors trigger shutdowns. Sometimes they reboot. Sometimes they die forever. And here’s the kicker: heat voids most warranties. So if your iPad went full sauna mode in the backseat? That $900 mistake is now yours to keep, along with the melted screen protector.

Still, we do it anyway. Because in a world where we multitask everything—from Spotify queues to conference calls—it feels inconvenient to carry our gadgets with us. So we leave them in the car like dogs we’re “just popping into the shop” for. And just like with dogs, the consequences come faster than we think.

Speaking of things that shouldn’t be left alone: sunglasses. And prescription eyeglasses. Especially if they’re left on the dash. What seems harmless—tossing your shades after a drive—can become a genuine hazard. Lenses, especially polarized or corrective ones, can magnify sunlight. That focused beam? It can burn fabric. Or melt plastic. Or, in rare cases, start small fires. Even if that doesn’t happen, the frames themselves can warp. The fit changes. The coating bubbles. Suddenly your $300 designer pair feels like a dollar store souvenir.

There’s also something quietly poetic about the way food turns inside a hot car. That leftover fast-food bag? It becomes a mini compost heap. Yogurt cups swell. Milk spoils. Bread molds. Cheese sweats. Not in the nice, charcuterie-board way—but in the sour, sticky kind of way. And while the smell is bad, the bacterial growth is worse. Especially in humid climates. Food poisoning doesn’t care that you “just forgot.” It doesn’t care that the AC was going to be on in a minute. Bacteria doesn’t wait for convenience.

But here’s where the contradictions start to show. Because in that same car with the rotting sandwich, there’s usually a bottle of water. Half-drunk. Rolling on the floor. Maybe three bottles, if you’ve had a busy week. And while it feels smart to have water on hand—hydration, always important—those plastic bottles don’t like heat either. When exposed to high temperatures, plastic can leach harmful chemicals like BPA and antimony into the water. The bottle might look normal. But the water inside? It’s now a slow drip of micro-contaminants. Not enough to kill. Just enough to linger.

If it’s not water, it’s soda. Or beer. Leftover from the beach run or a long drive. But carbonated cans in heat are notoriously unstable. They swell. They hiss. They burst. Not just leaking. Full detonation. The aftermath is a rainbow-sugar-syrup war zone. Upholstery soaked. Vents clogged. And unlike spilled water, soda doesn’t dry clean. It bakes in. You’ll be finding evidence of that Sprite until the next trade-in.

Let’s talk vanity now. Sunscreen, lip balm, foundation. These things aren’t just melting—they’re losing potency. Heat destabilizes chemical formulations. SPF weakens. Makeup separates. Lipsticks melt into tubes like wax in a candle shop. And medication? Same story. Most meds are labeled “store in a cool, dry place.” A glovebox is the opposite of that. If you’re storing birth control, insulin, or any temperature-sensitive prescription in your car for convenience, you’re not saving time. You’re gambling with efficacy.

Credit cards don’t get a pass either. In extreme heat, the plastic can bend. The magnetic strip can become unreadable. And those chips—the ones we tap every day—can fail. The most frustrating part? You don’t know it’s broken until you need it. That sudden decline at checkout? That’s the moment heat damage introduces itself. By then, it’s too late.

But nothing, truly nothing, should ever be left in a hot car more sacred than children or pets. This isn’t dramatic. It’s statistical. A child’s body heats up three to five times faster than an adult’s. Even with the windows cracked, a car’s internal temperature can reach deadly levels in under ten minutes. Dogs pant to cool down, but they can’t sweat. Their organs begin to fail quietly, invisibly, while you’re “just paying for petrol.” And yet, every summer, we still read headlines about children forgotten in car seats. Or dogs left with the window “slightly down.” The excuses always sound the same. The outcome never does.

And yet, we still treat the car like a sidekick. Like a mobile drawer, a climate-controlled locker, a storage unit with wheels. Our habits were shaped long before climate volatility intensified, before glass-roof sedans became norm, before temperatures started hitting record highs in places they never used to. The car became a safe space. Until it wasn’t.

There’s no neat solution here. But there is ritual. Parking in the shade helps. Sunshades—those silver accordion-folded ones that look like kitchen foil—do more than protect dashboards. They lower internal temperatures by several degrees. UV-blocking window films make a difference. So does cracking the windows slightly, if the car is visible and secure. Before getting in, open all doors for a minute. Let the hot air vent out. Let the seats breathe.

Then, when you start the car, don’t blast the air-conditioning immediately. Let it ramp. Sudden thermal shocks aren’t just bad for your body. They wear down the system. If you’ve ever gotten a headache after going from 40°C to 20°C in seconds, you’ve felt it.

There’s also a simple behavioral shift that might matter more than we think: treat the car as temporary. Not permanent. Don’t leave things “just in case.” Don’t let it become your second bedroom. Respect the space for what it is—a moving metal box that responds to the elements faster than we admit. Heat doesn’t negotiate. It just escalates.

And if we’re honest, there’s something comforting about the illusion that the car will protect our stuff. That we can leave our digital, flammable, edible, perishable lives behind glass and nothing will happen. But the sun doesn’t care about convenience. It doesn’t pause for errands or apologize for UV.

Maybe that’s what this checklist really reveals. Not just what to remove from a car in hot weather—but what we’re slowly learning to carry more carefully. How to respect heat as force, not inconvenience. And how to design small acts of safety into routines that were never meant to survive climate extremes. A car isn’t a fridge. Or a drawer. Or a vault. It’s just a vehicle. And in the summer, it becomes a test: of memory, of awareness, of whether we’ve outgrown the lazy idea that everything will be fine.

Most days, it will be. But on the day it isn’t, you’ll wish you’d taken the bottle, the phone, the medication, the dog—with you. Not just for safety. But because presence is the most underrated form of care. And in summer, nothing melts faster than our assumptions.