Light Flashes in the sky

I seen flashes of light in the sky in 1 spot. They were bright enough to light up the clouds in that given spot and would occur every 5-15 seconds for 1 hour. I called a nearby relative who went outside and seen the flashes were actually in 3 spots. The flashes repeatedly appeared in these 3 spots with no solid pattern detected.
2 hours later, I looked outside and the spot I noticed before had moved a lot closer but no longer flashing every 5-15 seconds and now more like every minute or so now.
A one point I heard what sounded like a helicopter outside.
This could very well be some very active heat lightning, though never seen a bolt. I also never heard of it being so active in the same few spots.
Witness elects to remain totally anonymous;  provides no contact information.  PD