Summer is very hot, especially in central Iran, where you are likely to go if you want to visit Iran for the first time, while winter is pretty cold and you’d rather enjoy provinces like Qeshm or Kish islands in the Persian Gulf unless you are into winter activities such as skiing.Autumn is mild in central Iran while it can be cold-ish in cities like Hamedan and quite pleasant in Tehran since the summer heat is gone. Prices will also be lower than in spring as it’s a less busy season.