Window leak

[whatsreallygoingon]

Hi all - twice in the last month during heavy rainfall/storms I've noticed a pool of water on the windowsill inside my back bedroom. Not a ridiculous amount, but enough for concern.

The window inside has two standard weep holes on each part of the window (top and bottom) - one at either side, but on the outside - it just has one central (in the pic).

Is that a normal weep hole setup for that type of window? And is that likely to be the issue?

A guy I know who fits windows mentioned condensation when I first mentioned it to him (haven't mentioned the weep holes to him, yet) but I can't see that. The house does get high relative humidity (which I'm in the process of addressing) but I'm yet to see any condensation on any windows, apart from tiny bits in the kitchen, and it hasn't really been cold enough for that yet.

 

[Wayners]

Mother in law had water on windowsill in upstairs bedroom.
I removed silicone outside. Masking over bricks. Pushed a plastic mastic nozzle over a foam gun and and jammed in around frame and squirted foam in, then more silicone around frame.
That worked for about 5 years then it started leaking again. New window fitted, and fitter said it wasn't sealed in properly. Been fine for last 3 years