Nooooo my Prime just expired. I thought I had a few more weeks.
Anyway. Last year I saw someone in here mention that they carry a flannel for latenights because it's way less bulky than a hoodie. Target has their winter stuff on clearance right now, and I saw lots of flannels on the rack.
Yes! Pack a lightweight flannel shirt. It folds up neat and small and will help keep the chilly night air off of your shoulders and arms.