My husband and I will be traveling to Barcelona on Nov 16 to visit our son who is studying there. Our daughter will arrive on Nov 19. The three of us will depart for USA on nov 26. We have not booked our tickets yet, but would prefer to travel roundtrip out of Barcelona. We will probably spend 3-4 nights in Barcelona and have heard wonderful things about Sevilla, but it might be not the best use of our time. I have also looked in to Montserrat and the Costa Bravo. I just don't know what this will be like in November and would love any suggestions.

Thanks

Seville is easy to get to by Vueling ( cheap flights).
Might be interesting to see something very different than Barcelona
or you can take a train to Valencia for a couple of nights.

Weather is impossible to foresee. You can be quite sure that it won't snow/freeze, and that it won't be 90F.
There is a good chance of rain/drizzle, but it can as well be warm enough to sit outside for lunch.
Evenings should be too cool to sit outside, or at least without a sweater/jacket.
Fewer tourists mean shorter or no lines at the major sights and museums.

Sevilla is no big deal to fly in. And November is quite fine down there. Though there is no guarantee for summer weather.
But, as you said yourself, you lose 1/2 day each time you fly.

Maybe you should also take into account that your son will have acquired a much larger knowledge thru his contacts with peers and locals than the average tourist. So maybe he will want to take you to places you can't anticipate now.

My daughter studied in Barcelona last fall & loved it. We visited her for 10 days. We spent 5 days in Barcelona; then we rented a car and drove up the Costa Brava, making stops along the way, & overnighted for 1 night in Cadaques (which is beautiful & our favorite place). Then we spent 2 nights in Girona, & drove thru the Pyrenees before returning to Barcelona. You can click on my name to read my trip report.

That sounds like what we are interested in doing. My son will be in class and so my daughter, myself and my husband will be traveling together. What month were you there?

Never mind. I see that you were there in October.