how many are you seeing? is it a big clump of them? do you know what a swarm looks like? have any photos?
if you've got a swarm of honey bees, you could call a beekeeper to come collect them or do it yourself. if it is honey bees, but not in a swarm, there might be a swarm hanging around somewhere sending out scouts or a colony preparing to swarm. in that case, a smell they don't like
should keep them from moving in. pine-sol and bitter almond oil are both decent options.
chances are reasonably good that they're some sorta of hornet or wasp, though, as this isn't really the main swarm season anywhere in the world. swarms do happen in August, but not terribly often. assuming you've got wasps or hornets, I've heard of folks hanging up an inflated kraft paper bag to simulate a paper wasp nest. some species are territorial and won't nest near an existing nest.