Windshield or sunroof leak?

I live in California where we don't get much rain, but this morning the sky really dumped on us. When I got in my Prius, I noticed a small leak on the passenger A-pillar. It's ONLY what you see in the picture. The water didn't drip, the footwell and headliner weren't wet... After it stopped raining, the A-pillar dried and it was like nothing happened.

I suspect it's either something with the sunroof drain or maybe the cheap aftermarket windshield the dealer put in for me three years ago has a loose seal or something. Has anyone seen anything like this? Thoughts or ideas?

 

@Rebound Thanks. I'll probably bring in a professional if it comes to pulling off the A-Pillar. I don't have a covered garage, unfortunately, and working around airbags kind of makes me nervous.

 

Quick update on this -- I took it to my autobody and they ran a two hour systematic water pressure test on the windshield and sunroof and couldn't find any leaks! I guess it's good news, but still seems weird. I'll have to keep an eye on it.

 

Update on this! It is STILL leaking when it rains. Oddly, it appears to be a different place every time (and sometimes appears to leak from the small side window, not the windshield; see photo from today's leak). I usually notice it after I have been parked on a crowned road, which explains why they weren't able to replicate it when a pressure test on the flat surface of the shop. I'm beyond frustrated with this, and hoping to take it back to the shop next week. @Rebound, I'll see if I can maybe try talking THE A-pillar cover off, but the guide you posted just says to look online.

I'm also still not sure if it's the drain channel for the sunroof or the windshield. The fact that it's leaking in different places lends me to think MAYBE it's the sunroof, but I don't know. Maybe I should just pay the money to have the windshield reattached and see if that fixes it? Grrr.

 

Update! I finally figured this out and got it fixed! Those who suspected replacement windshield were right! Apparently you need to place it with the sealant at a 45 degree angle and it was placed dead on, so it didn't fully seal in some sections. It had some kind of "lip" so it was only leaking occasionally and the lack of solid seal in several places is why it didn't always show up in the same spot. I got it resealed and now it seems fine. Woohoo!