Playa is always a place, where the best time of the year starts around thanksgiving.
It actually never ends really 
...,but the climate is best between than and march/april.
Never too hot, actually it feels kind of cold to me sometimes.
Obviously it is not as cold as a real canadian winter or a blizzard in new york....but as i said, it is not too hot here neither.
So if you want to come down this winter and see the white sandy beach, the turqoise water of the caribbean, the great restaurants on 5th Avenue, let me know and i make sure we arrange you a very helpful tour of seeing Real Estate in Playa del Carmen, Mexico.
There has been never before a moment when buying a property here would have been better.
Best Regards Alex