My apartment has turned into the Northwest Territories recently. I think it's the change in weather but something is forcing hundreds of flies into my apartment... and I don't know how they're getting in! I keep all my windows shut and have tried to close up any gaps I could think of but just keep on coming! I came home during lunch-time today and there were flies everywhere: between my window screens, on my tables, in my kitchen, etc. This pic is just a small sample of what I saw. They seem to only come in the afternoon because after I get home from work and its cooler out, most of them seem to have left. A few don't leave though and fly around my lamp and lights when I turn them on in the evening. I've been using my uchi-wa (fan) to kill them and then vaccuuming up the corpses afterwards but it's a pain in the butt. Does anyone know a way to kill flies en masse?