Like other tropical countries, Guatemala has two seasons: wet and dry. The former runs from May to October and features sunny mornings followed by showers in the late afternoon and evening. The latter, by contrast, extends from November to April and is characterized by hot days and cool nights. Many tourists opt to go during the Christmas holidays, when the heat and humidity are momentarily in abeyance, but visitors should be prepared for rain any time, especially in the areas along the Caribbean coast and in the rainforests of the Petén. This rain can occasionally make roads impassible, so if you’re heading into the jungle, plan ahead.
Temperature-wise, Guatemala is very predictable. The coasts are hot all year, while the highlands feature cold nights and strong daytime sun. As is typical in Central America, elevation, and not the season, is what determines how steamy things get. For example, the Mayan ceremonial site at Tikal, at 400 feet, hovers in the 80s year round, while Guatemala City and Antigua, at some 5,000 feet, enjoy temperatures in the 70s.
Average monthly temperatures (°F) and rainfall (inches) for select locations in Guatemala are shown below.
Source: World Weather Online.