The best time to visit Lyon is April to June and September to October, when temperatures are mild (15–25°C), restaurant terraces are in full swing, and the city isn't overwhelmed with tourists.
Spring (April–June): Pleasant weather for walking the old town and riverbanks. The Nuits de Fourvière performing-arts festival begins in June, running through July in the Roman theatres.
Summer (July–August): Hot (occasionally above 35°C) and busy, but lively. Many Lyonnais leave in August, which can make the city quieter — a double-edged sword if you want the full neighbourhood energy.
Autumn (September–October): Arguably the finest season. Temperatures are ideal, the Beaujolais Nouveau season kicks off in November, and the city feels like itself again after the tourist peak.
Winter (November–March): Cool and grey, but December is magical: the Fête des Lumières (around 8 December) is one of the world's great free public events, transforming Lyon for four nights. Book accommodation many months ahead for this period. January–February is the low season — good hotel rates, uncrowded museums, and the best chance of a last-minute bouchon table.