A tidal bulge is a bulge of water that occurs on the Earth's surface, primarily in the oceans, due to the gravitational pull of the Moon and, to a lesser extent, the Sun.

Here's what happens at a tidal bulge:

* High Tide: At the point directly facing the Moon (and to a lesser extent, the Sun), the gravitational pull is strongest. This pulls the water towards the Moon, creating a bulge known as a high tide.

* Low Tide: On the opposite side of the Earth, away from the Moon, the gravitational pull is weaker. This results in a slight "stretching" of the Earth, creating another bulge. This is also a high tide.

* Low Tide Again: Between the high tide points, there are areas where the water level is lower, creating low tides.

So, in summary, at a tidal bulge you experience high tide, while between two tidal bulges you experience low tide.