Spending the summer in Spain

How do you like heat?

While it does get hot in Madrid in the summer, after June 15th or so it's usually over 100 degrees in Sevilla every day. They usually get a hot spell for a few days where it's over 110 as well.

Love the heat, really don't mind those kinds of temperatures enough to sway my decision :)

It´s unclear what you mean by "little small", but if you don´t one another very big city, then just go Sevilla.

In any case, Sevilla is not small in terms of spanish cities, probably the 4th or 5th most populated, so I guess you should be able to find everything you need (including people and turist).

Food, bars, dancing places and so on you will find in almost any place in spain.

Madrid has far more inhabitants than Sevilla but far less than New York...

August isn't the liveliest month in Madrid as many locals go on holidays and you'll find many small business closed for holidays.

As you seem to be more leaned towards Sevilla, I think you should go for it. Don't worry about it being small for you, you can easily get out of Sevilla to tons of places (e.g.: on weekends if you don't work then). And you would be closer to the sea if that's of any interest for you.

I don't think Seville is really that small. When I think small, I think of places like Granada or Cordoba. Seville is rather big.

I don't mind the heat either, but Seville will be like walking on the sun. It wouldn't stop me from visiting, but staying a whole summer? I'd go for Madrid in a heartbeat.

I could spend a lifetime in Sevilla. I envy you with all my heart for having an entire summer to spend there.

that said, Andalucía has lots of great cities to visit, so you can be based in Sevilla and spend time in Granada, Cordoba, Cadiz and the many small towns around them.

I'm not a fan of the Andalusian beaches (Malaga and surroundings, Almeria, Marbella, etc.) but many tourists go there so that's an option.

Madrid is completely different from NYC, and sure enough you can spend another lifetime enjoying it. That said, it really, really pays off knowing enough Spanish to communicate with the locals. Madrid's greatest asset is its people, not any landmark or sight. If your Spanish is limited or non existing, you will not enjoy the city anywhere near its potential.

Madrid is not at all like NYC. The look of the neighborhoods has changed remarkably little over the years. it has a modern, youthful energy and a blast of culture, but you are unmistakably in the heart of an old, classy European city with an array of plazas linked by boulevards and tiny streets.