Aside from snaking the drainage tube, the most common clogging issue is due to the s*** design of the part where the water drains out. The part in question is 74816-JU40B and I've had to replace this for my G37 and the wife's 2015 Rogue. Gunk builds up over time and solidifies and clogs the drainage spout.
If you don't want to replace the whole part then you can follow the excellent suggestion here:
https://www.youtube.com/watch?v=H_60eHcPjUw
(Not a promo)
Basically, you are clipping off the plastic thing at the end of the moonroof drainage tubes on the engine side of the firewall. This should work but I noticed that when I was doing this for my 2012 Infiniti, the ring seal was coming apart so I replaced the entire part. On the Infiniti, you can't easily get to the firewall spout area so it's best to replace the part. It's $10-$15 depending on where you get it from and it's about an 1 hour work to replace and reassemble. I did clip the plastic spout blocker on the new parts before I installed them.
Even if you're not sure your floor is dry, I strongly encourage you to check in the side boards on both sides under the carpet for where water might be trapped. It'll get nasty quick and your car will smell like your old high school gym locker in no time. Not to mention an obscene amount of fogging inside your car for at least a year. Clean it well until it's dry and make sure the styrofoam down there gets dry as well. I found some new life forms starting their own evolutionary track because I waited too long to check why my car had the odor of a toad graveyard.