Is Spain & Portugal Good to visit during November?

Where in these countries would you be going? Northern Spain, southern Spain. The weather is different depending on where you're going, especially for Spain, which has more geographical differences in weather because it's bigger.

I am planning for Barcelona and Madrid. I guess they belong to north spain

POrtugal - I am planning for either porto or lisbon.

We have at least two contributors who live in Spain, who may see your question and be able to give you more precise information. In the meantime, if you haven't already done so, there are numerous websites that give "average" weather by location and month. Averages are the best you can do now, because really no one can tell you what the weather will exactly be when you go. But you can get an idea.

In just a quick look at one weather website, I'm seeing:

Madrid
November is one of the three rainiest months in Madrid, 10 days in Nov. have some rain, on average. Day time temps average mid to upper 50's F.

Barcelona
Surprisingly (to me), Barcelona is about the same as Madrid, I thought it might be different because it's on the Mediterranean, but at least in November the temp range and rainfall is similar to Madrid. Except that in Barcelona, the rainiest time is August - October, with the single rainiest month, on average, being in October (which is obviously close to Nov.).

You should look at a number of websites to get a better idea.

Pretty much any time is a good time to go, depending on what you want to do. Since you are apparently going to cities, then time of year isn’t much of an issue. Just dress accordingly. Obviously, the beach wouldn’t be great in November, but you could still walk along the one in Barcelona. All the historic monuments and museums will be open,

I'd want to look at actual day-by-day temperatures in November going back at least 3 years. That will give you a much better idea of the temperatures you are likely to experience than monthly averages. You can find that information on timeanddate.com and wunderground.com.

A quick check of Wikipedia's average highs and lows (which cut off in 2010, making them suspect) reveals that Barcelona is likely to be substantially warmer than Madrid in November.

"How about historic places, museums and so on? will it be open during that time?"

Yes, open. 1/11 is All Hallows Day (in both countries, I think), when some shops and most commercial businesses, like banks, will be closed, but I doubt any tourist attractions will be. Unless there is a regional holiday, I think you'll be fine throughout November - even if there is a regional holiday, everywhere doesn't close, since that's a day local families want to visit.

I wouldn't worry about the weather either. Depending on what you're used to, it might feel quite warm during the day - colder later on when the sun drops. Madrid - compared to Barcelona - especially gets pretty chilly in the evening (less "coastal warmth" effect - this also means averages covering 24hrs are unhelpful, they include the middle of the night when it might be under 5°C, but you're asleep). Expect that it'll probably rain a bit at least at some point - more in Lisbon & Porto than Madrid or Barcelona. But, unless you're unlucky it won't be torrential or lasting all day, more showers. And rain is nature's way of saying it's time to find a bar and go inside for a drink.

Thanks so much Kent for your detailed and quick reply.

Thanks jaimeelsabio for the info.

haha, Thanks Nick for answering my question and specifically about that hallows day.

All your responses were helpful. Thanks.

As mentioned, a website like wunderground gives specific temperature and precipitation for the dates your are wanting to go. Look for the past 3-4 years. There has been some weather changes hotter temperatures in Andaluscia and elsewhere. I was in southern Spain and Madrid to Valencia (south of Barcelona on the coast) for 3 weeks from late October to mid November 2017. I had 2 days of rain in Seville early in Nov but it was still drought conditions throughout all of Spain. Nov 9 is Madrid's patron Saint day. The processions are interesting. Some things may be closed, but tourist sites are open. It was quite cool requiring gloves and hat, but sunny and bright. South of Madrid was t-shirt weather.
Coming into November, some sites might have slightly shorter visiting hours, but these are major cities, so they won't be ghost towns.