Best time to visit Perpignan
Perpignan has a very warm and dry climate, with pretty steady weather. Thus the coldest months in Perpignan are January and December, if you can call a mean low temperature of 4-5ºC cold, while the warmest (meaning really hot) months are July and August with a mean high temperature of about 28-29ºC. Generally, though, in usual year conditions, the city is welcoming.
You can also enjoy the fine weather and strolls on the old narrow streets in spring, when the evenings are mild and the mornings still shiny. This is also when most of the street events in Perpignan actually occur.
