Weird loud sounds. Typically a jet/plane sounds like it's low, then loud (when it's above/near you, then low again. Just 5 minutes ago the sound was all over the place, it was loud, then low, like it was circling or something.
Something is definitely happening!
Could it be those new stealth bombers cruising around or other such military aircraft for surveillance? I live sorta close to a small military base and every once in a while, when a jet is on the ground, they will sit there "revving their engines" I honestly do not know what they are doing when they do it, just know the sound can go on for quite a while at times.