Playa del Carmen weather is pleasant year round, so there is really never a bad time to visit. This Mexican beach town enjoys a sub-tropical climate, and for the most part, temperatures stay in the moderate to warm range.
Winter: When northerners start to get tired of snow and ice during the winter, they often start dreaming of an escape to somewhere warm and sunny. Playa del Carmen is one such destination. In the winter, the daytime temps in Playa tend to climb up into the 80s, and the sun is most often shining. At night, the temps tend to dip down into the 70s and 60s, and since it can get cooler on occasions, you will want to grab a sweater or jacket when packing. In general, winter is considered to be the best time to travel to Playa del Carmen. It is a particularly dry season, which only lends to the popularity of winter visits.
Spring: Spring can be a fantastic time to visit Playa del Carmen. The days are warm and sunny, and should you be planning on doing things like scuba diving, the Caribbean Sea stays calm and clear. Daytime temperatures in the 80s and 90s can be expected in Playa during the spring season, and while it can get cool at nights, it isn't usually isn't a significant enough drop to warrant a jacket or sweater.
Summer: Two words can accurately describe the Playa del Carmen weather during the summer season: hot and humid. Sure, it is usually hot and humid in the Caribbean throughout the year, but the June to August period takes this to another level. Temperatures of 100 degrees are possible during the hot summers, so relaxing on one of the Playa del Carmen beaches or kicking back poolside are the most popular pursuits. May to October is the rainy season in this part of the world, so you can expect an increase in showers, but the showers don’t last long.
Fall: As the rainy season wears on in Playa del Carmen region, the chance that a tropical storm or hurricane might move in increases significantly. That being said, tropical storms and hurricanes are relatively rare events in Playa del Carmen, though you should look into travel insurance either way. One of the advantages to visiting in the fall is that you won't have to deal with the winter and spring crowds. You might also find that the cooler weather that storms often bring in the fall can make for a more enjoyable experience when doing things such as climbing the Mayan ruins near Playa.