Weather this past May in Portugal

You can see the weather history for any cities on weatherspark.com or wunderground.com or several other websites.

Thanks Roberto!

I was there all of may this year, the first few days were in the 60's and warmed up quickly, we had 4 more weeks of perfect weather. If you are staying for any length of time,do yourself a favor and get a transit pass and take the local commuter train up the coast.

The weather varies depending on where in the country you’re talking about. Rather than trying to generalize for an entire country, use the mentioned websites to look at weather in the places you intend to visit. The weather this past May may be completely different next year. Hot, cold, rainy, or sunny, I’m sure you can make the best of it.