I see you live in Spain. Unless the aircraft you intend to train in have air con, training between October and May would be best.
The summer heat can be oppressive without air con.
Light aircraft performance is better in cooler climates, less convective air outwith summer, and the possibility of better training conditions in the ME phase with icing and cloud to deal with.
Flying in cloudless skies might be ideal for the first 50 hours, but to become a “rounded pilot” you need exposure to weather. One advantage of training in temperate latitudes.