A distinct division between rainy (November to April) and dry (May to October) seasons makes winter and spring months the ideal time to be in Antigua. This is also prime time for Antigua's many religious observances, the most famous of which is Semana Santa (March or April). Holy Week brings a series of daylong vigils, processions, and reenactments of Christ's last days in Jerusalem. You'll see Roman centurions charging through the streets on horseback, boulevards carpeted with colored sawdust and flowers, and immense hand-carried floats wending their way through throngs of onlookers. Make reservations months in advance if you plan to be here for Semana Santa.
Antigua's tourist population increases dramatically on weekends as Guatemala City residents head out from the capital to their favorite destination. The city fits nicely into the beginning or end of your trip. Its proximity to Guatemala City's La Aurora International Airport makes it a good first or last place to visit.
The highlands have distinct rainy (May to October) and dry (November to April) seasons, the latter of which offers the best weather conditions for outdoor-market shopping, lake boating, and volcano hiking. Travel during the rainy season is rarely a hardship; it usually rains just for a couple of hours in the afternoon. Evenings get chilly enough for a jacket, and can get downright cold the farther west you travel. In December and January temperatures dropping to near freezing at higher elevations. That said, the highlands have no weather-based high and low seasons per se. The region does see a greater number of visitors in July and August, and during Christmas and Holy Week.