Hi , I've already posted this into another place on this forum , but I think that it best fit in here so I reuploadit :
Hi everyone!
First of all , I apologize for any grammatical mistake I make but my maternal language is not English .:dry:
Anyway , I'd like to know if anyone has ever had any experience on having a Japanese Maple bonsai (Acer Palmatum ) in Barcelona, Catalonia ( Spain) or any other Mediterranean Climate as mine, or If you think it will succeed.I already have one Japanese Maple variety 'Seiryu' and another one without any variety , which I think it's called Yamamomiji , but both of them are grown as a garden plant ,not bonsai.
Anual average temperatures are about 5°C(41°F) as the minimums and the highest temperatures are about 35°C(95°F). Despite we sometimes reach temperatures about 0°C(32°F) or 38°C(100°F).Relative humidity is very high during all the year , about 65% during day and specially high at night , reaching easily 80% even when it is not raining. My maple tree would have sun from the very early morning till midday .
Thank you very much , I'll wait for your answers

Your Maple should be fine. The temperatures are not too high and can take much lower. The amount of sun is fine too. The main thing is to keep it well watered in the summer months. They can take sun as long as the roots have water.