Early autumn often keeps summer-like weather with slightly fewer tourists than July/August. The Yacht Show draws industry visitors and exhibitors each year.
Average temperature across Monaco in September.
The first cool breaths of autumn arrive in September, with temperatures easing back into the low to mid‑20s and sea temperatures still pleasant for evening swims. The Monaco Yacht Show draws marine traffic to the harbour and makes the waterfront busy; late‑month storms are still uncommon but possible. Travelers will find shoulder‑season advantages - fewer queues than peak summer and very agreeable weather for strolling the Casino gardens.
Early autumn in September leaves the eastern seafront comfortably warm and far less crowded than in August; sea temperatures stay pleasant and yachts still frequent Port Hercules. The Monaco Yacht Show in late September concentrates maritime traffic and brings a cosmopolitan bustle to the waterfront. Bring a light jacket for cooler mornings and enjoy longer windows for swimming and watersports.
By September the harbour cools into agreeable temperatures and yachts remain plentiful; the Monaco Yacht Show adds a businesslike bustle to the quayside in late September. Occasional autumn storms are still possible but most days are perfect for harbor walks and al fresco meals. Bring a light jacket for evenings and enjoy quieter mornings at the Condamine market.
Upper Terraces
September is excellent up on the Rocher: milder temperatures, clearer air, and far fewer visitors than in high summer which makes palace and garden visits much more enjoyable. The Exotic Garden benefits from retained warmth of summer and late blooms; clear days offer excellent vistas of the bay. A light jacket is often adequate for early mornings and cooler nights.
A major annual yacht and luxury marine exhibition held in late September in Port Hercules.
See how September compares with the rest of the year, then read the full guide.