Lanzarote's Carnaval in February or March pales slightly compared to Tenerife or Gran Canaria, but is still celebrated with great gusto.
Peak periods are Easter, July, August (20°C to 28°C), December and, to a slightly lesser extent, January/February (20°C to 24°C). Book well ahead and expect increased hotel rates, car-hire queues and crowds at the main sights and national park.
March and May (excluding Easter) are quieter months, while late-September and October are perfect for warm weather with fewer crowds.
Hiking is great almost year-round, apart from hot July, August and September.