Hail suppression cannon for the booms, not sure about the whistling noise.
Ah, I bet you’re right. It fits with what I found when I searched “hail suppression cannons”. I’d never heard of them.
I was thinking geese suppression cannon, but those are usually spaced further apart.
I wonder if that whistling noise is made by some sort of projectile cutting through the air after being fired from the cannon?
I agree - sounds like hail cannons. We get them sometimes.
I think the other sounds are being created by the vibrations from the cannons and it sounds to her like they’re going in a circle. Low clouds probably causing some of the conditions for the other noises.