Honestly looks like a malfunctioning app to me. With propagation effects, the strongest radar returns should naturally be closest to the center of the circle with weaker returns as you go farther out.
In this case you’ve got strongish returns right up to what looks like the edge of the radar’s unambiguous range and basically no returns towards the inside… Which I don’t think represents any real phenomena. Looks more like the app is incorrectly rendering (or not rendering at all) the higher value radar returns, leaving that weird ring. Notice how there are some splotchy lower value returns towards the center though, which would be expected under normal circumstances.
Honestly looks like a malfunctioning app to me. With propagation effects, the strongest radar returns should naturally be closest to the center of the circle with weaker returns as you go farther out.
In this case you’ve got strongish returns right up to what looks like the edge of the radar’s unambiguous range and basically no returns towards the inside… Which I don’t think represents any real phenomena. Looks more like the app is incorrectly rendering (or not rendering at all) the higher value radar returns, leaving that weird ring. Notice how there are some splotchy lower value returns towards the center though, which would be expected under normal circumstances.