We were there for the first week of March and most of the days it was warm enough for t shirts and towards the end of the week it got very warm, much better than home. It did get chilly at night though and you would need a jacket or jumper.
Nearly everything was open and plenty of bars etc. The only thing we couldn't do was go on the cable car as most days it was too windy for it. We've booked again for next year at the same time.