Why gutters may overflow in heavy rain
Visible overflow can relate to debris, a restricted outlet, standing water, alignment, or the collection and discharge layout.
Direct answer
Observe where water crosses the gutter edge from a safe position. The visible symptom does not identify one cause by itself.
What to check safely
- Watch from a safe position: Note whether water spills at a corner, along an edge, behind the gutter, or near a downspout.
- Check after rainfall: Look for visible debris, standing water, or loose sections.
- Record the discharge area: Note where the nearby downspout releases water.