Lisbon edges it in May. Lisbon averages 14–23°C with medium crowds; Porto 12–20°C with moderate-high crowds.
By Daan · Last reviewed October 2026
Lisbon and Porto
The verdict for May
One of my favourite months
+Warm enough for rooftop drinks and long evenings, without the full summer crowds.
–The sea is still cold if you are planning beach days.
Rooftop season starts and the city has not filled up yet.
Warmer days, rising demand
+Pleasant temperatures for sightseeing.
–More visitors and less predictable weather than summer.
May brings warmer afternoons and longer days, but rain is still possible. Visitor demand builds towards summer, and major university celebrations can affect activity and accommodation demand on particular dates.
Scores and crowd levels are my own judgement; temperatures are monthly averages. Higher scores are better: quieter, cheaper and more pleasant.
Another month