August is Casablanca's peak summer, yet it stays remarkably comfortable. Daytime highs around 26°C, tempered by the constant Atlantic breeze, keep the city far cooler than the inland heat of Marrakech or Fes. The summer haze pattern continues — greyish mornings burning off to bright, warm afternoons — so the seafront and beaches reward a later start, and warm evenings stretch long along the Corniche.
It is the height of beach-city season. Ain Diab's clubs and pools are at full tilt, the Corniche is busy with families into the night, and the Hassan II Mosque's seafront esplanade is a fine spot for the cooling breeze and the Atlantic sunset. Casablanca's warmth is gentle enough that the central market, the Habous quarter and the Art Deco downtown remain easy to explore even at midday, with none of the inland furnace.
For travellers and families seeking a genuine summer-by-the-sea without Morocco's interior heat, August is a strong choice — lively, warm, breezy and forgiving. It is busy on the coast and at the beach clubs, so book ahead, but the city itself rarely feels overwhelmed, and the Atlantic keeps the whole experience comfortable from morning haze to warm starlit night.