10 Smells That Get Worse When It’s Hot Outside

When the heat rolls in, some smells don’t just show up—they get worse. High temps can speed up bacteria growth, intensify chemical reactions, and pull odors out of things you didn’t even realize could stink. And once that smell gets into the air, it lingers. If your house, yard, or car has been smelling off lately, one of these common culprits might be to blame.

Garbage Cans

Heat makes trash ripen fast. Whether it’s kitchen scraps, meat packaging, or diapers, warm weather speeds up decomposition and brings the smell front and center.

Even if you’re taking the trash out regularly, the can itself can hold onto odors. Clean it with vinegar or diluted bleach, and let it dry in the sun to cut down on the stink.

Litter Boxes

Cat litter already isn’t great, but add heat to the mix and it can take over the whole room. Ammonia in urine gets stronger in warm temps, and clumping litter holds onto it.

Scoop daily and give the entire box a rinse once a week in summer. You might also need to upgrade your litter if it’s not holding up to the heat.

Dirty Dish Sponges

A sponge in a hot kitchen is the perfect breeding ground for bacteria. If it starts to smell sour, that’s not something you can rinse off—it needs to go.

In the summer, you may need to replace sponges more often. Or switch to a brush that dries faster and doesn’t trap as much moisture.

Pet Bedding

Your dog might be clean, but their bed can smell like wet fur and drool when it’s hot outside. Foam inserts especially tend to hold onto that musty, baked-in pet odor.

Wash the cover regularly and let it dry completely in the sun. If it still smells after washing, the inside padding might need to be replaced.

Drains

Bathroom and kitchen drains can smell worse when it’s hot, especially if there’s a clog or slow buildup inside. The heat speeds up bacteria growth and makes that funky odor rise faster.

Flush your drains with hot water and baking soda regularly. If it still stinks, a deeper clean might be in order before it becomes a bigger issue.

Laundry Left in the Washer

Letting a load of laundry sit for even a few hours in the summer can turn it musty. Heat makes mildew grow fast, especially on damp towels or athletic wear.

If you forget a load, wash it again with vinegar before drying. And try to set a timer if you know you’ll get distracted mid-cycle.

Compost Piles

Compost is supposed to break down, but when it’s unbalanced—too wet or packed with food scraps—it turns sour quick. Add heat, and that earthy garden smell can shift into full-on rot.

Keep your pile balanced with dry material like leaves or cardboard, and turn it often. That airflow helps keep the smell under control.

Outdoor Trash Bins

Your big outdoor bin can cook in the sun all day long. Even a small amount of spoiled food or liquid in the bottom can lead to a powerful stink cloud.

Rinse the bin monthly in summer and leave the lid open to dry. Sprinkling baking soda in the bottom can help absorb moisture and odors too.

Refrigerator Drip Pans

Some fridges have drip pans underneath that collect condensation. When those pans go unchecked, bacteria and mold can start to grow—and in the heat, that smell can leak out fast.

Unplug the fridge and clean the drip pan at least once or twice a year, especially in warmer months. It’s one of those behind-the-scenes jobs that makes a big difference.

Carpets After a Spill

If anything wet soaks into your carpet—milk, juice, dirty mop water—it can start to sour when it gets warm. That smell often hides until the room heats up.

Use an enzymatic cleaner for spills, especially anything organic. If the odor keeps coming back, the padding underneath may need a deeper clean or replacement.

*This article was developed with AI-powered tools and has been carefully reviewed by our editors.