Spring (March–May): culture and wildflowers
March and April are warm and bright (18–24°C on the coast, 22–28°C in the south) with the cork forests of Khroumirie and the Cap Bon hills in full bloom. Rainfall drops sharply after mid-March. This is the best window for Carthage, El Jem, Dougga and the Bardo without queues.
By mid-May the sea has warmed past 20°C, days reach 27°C, and the first beach guests arrive. Prices are still well below summer rates.
Summer (June–August): beach season
June is the smartest beach month — sea at 22°C, days at 28–30°C, hotels at 60–70% of August prices, and no school crowds. July climbs into the low 30s on the coast, and August peaks at 32–34°C. Resorts run at capacity, charter flights are full, and the desert becomes punishingly hot (45°C+ in Tozeur and Douz; avoid).
If you visit in August, choose Cap Bon (Hammamet, Nabeul, Kelibia) or Tabarka in the north — the breeze keeps things bearable.
Autumn (September–November): the sweet spot
September is arguably the single best month of the year: the sea is at its warmest (25°C), days hover around 28°C, crowds thin out, and prices begin to slide. October stays in the mid-20s with a few rain showers. By November the coast cools to 18–22°C and beach hotels close their pools, but cultural circuits are perfect.
Winter (December–February): Sahara and city breaks
Winter on the coast is mild (13–18°C by day, 7–10°C at night) with the most rain of the year, concentrated in December. The flip side: Tunis, Sousse, and Hammamet are quiet and cheap. The interior is cold at night but glorious by day, with crystal-clear light over the Roman ruins.
The Sahara comes into its own from late October to mid-March: daytime 18–24°C, cold but starry nights, no risk of heatstroke on camel treks.
Our recommendation
If you want one answer: book the first half of June or all of September. You get the warmest sea, dry weather across the country, all attractions open, and prices 30–40% below August.
For a desert-focused trip, October–March. For a culture-only trip, April or November. Avoid the last two weeks of August unless you specifically want crowds and high prices.