The rainy season is between May and October, with the heaviest rainfall mostly in June, September and early October. During the rainy season the days often start dry and fairly bright, and there’s usually a heavy downfall in the afternoon. Tabasco receives particularly heavy rainfall (about 1500mm annually).
Between November and April, warm sunny days are the norm. The hottest months are April and May, when the fields turn a dusty brown before the onset of the rains.
Temperatures in Tabasco and Chiapas don’t vary much according to the season – altitude is a much more influential factor. All lowland areas (most of Tabasco, the Lacandón Jungle, Palenque, the Usumacinta area and the Pacific coast) are hot and sticky all year, with punishing humidity and daily highs above 30°C. In the more elevated center of the region, the climate is less enervating.