I will be travelling to NYC mid September 2014 and will stay till the end of the month. The temperature predictions show variation from 80 to 50 deg F. What kind of coat or jacket would you recommended? Will a hip length 50% wool 40% polyester coat do or is a trench better suited? I hail from the tropics and am not used to chilly weather and don't understand warm clothing either. Any inputs appreciated..thanks!