I think it might be cooler:
Accuweather.com for Istanbul:
................high.........low........
Oct 4th .....54......... 45......... stray morning shower, windy
Oct 5th......55......... 44......... cool with clouds and sun
Oct 6th......55......... 47......... clouds and cool with showers
Oct 7th..... 64......... 55......... sun then clouds
Who knows.... no matter what the weather... I can't wait!!!!!

Safe travels tomorrow, Olivia!