Best months to visit Playa Larga are November/December through April. The reef at Playa Larga is close to the shore.
SNORKELING: The best time for snorkeling is in the morning with calm sea. Towards the afternoon the sea becomes rough. WEATHER: The best climate is during the dry season (from November until April). May and June is worth a try. Avoid July until October, it's rainy season and there is a higher chance for hurricanes. TOURIST CROWDS: July and August are the Cuban summer holiday and it might get crowded in general. Usually Playa Larga itself isn't that crowded at all. There are casa particulares only, not even one big hotel.
In April female land crabs start to migrate from forests to the sea to release their eggs. Masses of red and orange crabs are heading to the sea and back.
Best month for the crab migration is April but you may see them until June.