The high season in Mykonos, Greece, occurs during the peak summer months of July and August. During this time, the island is at its most vibrant and electric, with world-famous beach clubs like Scorpios and Nammos operating at full capacity. Temperatures typically range from 25°C to 30°C (77°F to 86°F), providing perfect weather for Mediterranean swimming. However, this is also when the island is the most crowded and expensive; hotel rates often triple compared to the off-season, and dinner reservations at popular spots in Mykonos Town must be made weeks in advance. If you prefer a balance of good weather and "breathing room," the "shoulder seasons" of June and September are increasingly popular in 2026, offering warm seas and open venues but without the overwhelming peak-August density. By late October, the high season concludes, and many of the island’s signature parties and luxury boutiques begin to close for the winter.