The Tropic of Cancer divides Mexico into a tropical south and temperate north, which means that the northern region experiences cooler winter temperatures, whereas the south is hot all year with little seasonal variation. The coastal plains and Yucatan Peninsula of the south experience average annual temperatures ranging between 75°F and 82°F (24°C and 28°C). The annual average temperatures in the northern lowlands are somewhat lower, ranging between 68°F and 75°F (20°C and 24°C), mainly because there is greater seasonal variation. The whole country tends to be hot and humid between May and August and is pleasantly warm throughout the year. Rainfall varies widely according to region and terrain, but Mexico does have distinct wet and dry seasons: most of the country experiences a rainy season between late May and mid-October, with significantly less rain the rest of the year. February is the driest month and July is the wettest. Hurricanes are possible between June and November.

The best time to visit Mexico is between November and early May. It is best to avoid the peak summer months (June to August), when it is uncomfortably hot, and the Easter holidays (March and April), when it can get unbearably crowded.