Warm weather and weekend block parties come some unwanted kitchen pests. Yes, as your kitchen grows more hot and humid, tiny fruit flies will inevitably start showing up.
The fight against fruit flies starts with the fruit itself. Fruit flies get into your home by coming in on pieces of fruit you bring in from the store, so when you first notice the flies, toss any overripe fruit you may have sitting out on the counter and promptly take out the trash. Store any new produce in the fridge until the infestation is gone. Then clean any containers or surfaces, making sure not to forget the bottom of your garbage can and the drain of your kitchen sink.
If the flies persist, you can set up a trap by pouring apple cider vinegar into a microwave-safe bowl. Add a few drops of dish soap and microwave for 30 seconds. Sit the trap on the counter for a day or two. The warm aromatics of the vinegar will attract the flies, and the dish soap will break the surface tension so that once a fly touches the liquid, it will fall right in.