The dry season runs from January to June, with the sweetest conditions between February and April — low humidity, trade winds keeping temperatures around 27°C, and little rain. July through November is hurricane season; August and September are the peak risk months. Rain falls more intensely during the wet season but rarely all day — showers tend to be sharp and short.
The island hosts its biggest festival, the Carnival of Marie-Galante, in the days before Ash Wednesday (February or early March). Street parades, traditional Gwo Ka drumming, and costumed groups fill Grand-Bourg. It's rowdier and more local-feeling than the Guadeloupe mainland carnival.
Fête du Rhum celebrations coincide with the distilleries' harvest season, typically January to June, when fresh cane is being pressed and the new-season rum begins fermenting. Visiting a distillery during this period means seeing the whole process in action rather than just the ageing barrels.
Easter weekend draws Guadeloupean families to Marie-Galante's beaches — the island gets noticeably busier and accommodation fills up. Book ahead if travelling then.