I am thrilled that I will be in Cologne and Vienna for two weeks in the middle of September. Temps should be between 20-30C/50-70F. We never have mild weather like that where I am (it is either scorchingly hot or much much cooler), so I am at a bit of loss as to what that actually feels like, and what to what to bring for outwear. Will it be cool enough for a leather jacket? Will I want boots and jeans? Or dresses and sandals? Or in between? Advice requested!

(My dress code will be academic/business casual/touristy. My husband will be attending an academic conference in Cologne and then in Vienna will (hopefully!) be setting up a sabbatical for next year. So while I'll be playing tourist and want to be very comfortable, I'll also be playing "the professor's wife," and will need to be pulled together and appropriate.)