Málaga has the warmest winter of any city on mainland Europe and over 300 sunny days a year. The shoulder seasons — April–June and September–October — are the most pleasant: temperatures of 20–28°C, sea warm enough to swim in, and the crowds thinner than midsummer.
July and August are very hot (35–40°C is common, occasional spikes above 43°C) but the constant Mediterranean breeze keeps the coast bearable. This is also when the Feria de Málaga takes over the city for nine days in mid-August — a continuous open-air party of flamenco, sherry, fairground rides, and horseback parades, held first in the old town by day and then on the fairground south of the river by night. Winter is mild (averages around 13–17°C, lows rarely below 8°C) with occasional rain in November and December; even in January you can sit outside at lunchtime in a T-shirt.
Other dates worth planning around: Semana Santa (Holy Week, March or April), one of the most spectacular in Spain — vast wooden floats carried through the streets by hundreds of bearers, most famously the Cristo de Mena escorted by serving Spanish Legionnaires; the Málaga Film Festival in March, the country's main showcase for Spanish-language cinema; and Picassian October, a month of exhibitions and events around the artist's birthday on the 25th.