I agree about the Showers Pass jacket. When I rode in Vermont last month, the temperatures and conditions were similar on the last day. In fact, the temps were going down... I wore a short sleeved jersey with short sleeved base layer, arm warmers, and leg warmers that had a thermal inside. I didn't have tights with me, as the forecast didn't require them. Wool socks, toe covers. I did not have a helmet cover, and wore a regular beanie, lightly thermal.
Even with the pit zips open (the zipper is stuck on one side and is always open), I was sweating. I mean, it was 48 at the end of the 26 miserable miles that day, and it misted/rained for at least half of those miles. But, I was very glad I had the jacket, because I was dry!