Every year in May ‘Out Jazz‘ begins. This is a brilliant idea which has grown tremendously in popularity. It began in 2006 as Sunday afternoon jazz in the parks of Lisbon, moving to a different park each month from May until September. There is a live band starting at 17:00 and finishing around 18:30. This is followed by a DJ who plays until the sun disappears completely. Traditionally, Jardim da Estrela, which has a ready made band stand in it, was the park to host the first month of jazz. Some of the other parks (Parque Eduardo VII for example) have a makeshift bandstand brought in.
You can take something to eat, a picnic blanket and some friends and lie in the sun while allowing the mellow music to flow over you, regenerating in time for Monday. This event has become extremely popular and much busier and is now sponsored by a number of big brands. You can now buy food (hotdogs) and wine or beer at each venue, although I think there is still something much more romantic about taking your own picnic.
As well as going to the park jazz on Sundays, you can now enjoy jazz on Friday after work at 18:00. This venue moves every Friday and the list of venues can be seen in the link below. The venue for the month of June is Anfiteatro Keil do Amaral, Monsanto.