In New York the temperature can vary 15 to 20 degrees from morning to midday and back to evening. If you add to that to walking in and out of the direct sunlight and the shadow of buildings, dressing in New York City during the early Fall can be a many layered dilemma. By the same token one of my pet peeves each Fall are those people that just can't wait to breakout their new coat or chunky sweater at the first chance it may drop to 72.
The other morning at around 8 am I saw a young lady at Starbucks with a sweater, puffer vest, and scarf - I think it was around 68 at that moment and going up to 75, bet all those layers were gone by 10 am.