Sunday, October 25th had a very heavy downpour - perhaps as much as 30 mm of rain fell over a period of an hour. Hard to say without a rain gauge, as the weather stations in this area missed the heavy fall, as it was quite a small cell moving through. Nearby falls were just a few mm at Bankstown Airport, much the same at Lucas Heights, but over 30mm at Sydney Airport (closest stations to home).
During this downpour, I noticed water running down the exterior walls of my home, but could not determine the path the water was taking to reach there. There were two locations, both in the courtyard between the master bedroom and the dining room. The "flow" was below the beam forming the lower (western) end of the Vergola.
This is what attracted my attention - water running down the wall.
A closer view of the start of the flow down the wall. At first I thought it might have been coming from the outside of the downspout, but it wasn't.
This closer view shows it apparently coming from the wooden beam forming the lower end of the Vergola support structure.
A view from the outside. This was difficult to get because it was still raining!
I also noticed the same pattern happening at the other end of the support beam.
Close up view of that end. The flow did not seem as strong at this end, but that may be just that this was the last photo I took, and the heavy rain had passed, and the flow was diminishing.