I am going to Barcelona April 20-28, 2019. What type of clothes should I take? Thank you in advance for help.

For historic climate data, see weatherbase.com

You can be assured it will not be cold in Barcelona in April. It has a Mediterranean climate. It's now the end of January. The average daytime temperature for the next few days will be 60ºF/16ºC, sunny with a chance of rain. By April is could be in the 70s, with the possibility of a little rain.

April can be a bit hit and miss concerning precipitation in Barcelona, however, what I can say for certain is that the temperature is in every case great. April/May is the point at which the climate starting heating up and in April you can cheerfully stroll around in bright climate. Easter is a decent time to visit Barcelona somehow or another and in different ways, it isn't. There are fewer vacationers at Easter than in the summer thus touring will be much less problem free.

Thank you so much for your responses which will help in not packing heavy clothes!

I've been to Barcelona in February and was in shorts and t-shirts much to the bemusement of the locals.