Summer is the peak season, with warm seas and long days from June to September. July and August are busiest — book accommodation well ahead, especially if you want anything near the beaches at Lopar.
June and September are the best months: the sea is warm, the crowds are thinner, and prices drop noticeably. The island is green and lush on the sheltered south and west sides even in the height of summer.
The Rab Summer Fiera (25–27 July) is a medieval festival held in the old town's Kaldanac quarter, with costumed processions, traditional crafts, and a crossbow tournament. It is the highlight of the island's cultural calendar.
Outside the summer months, Rab is quiet to the point of emptiness. Most restaurants and beach bars close from October to May. The old town remains open year-round and is worth a visit in spring, when the bura (the cold northeast wind that strips the northern side of the island bare) has eased and the pine forests on the sheltered side are at their most vivid.