What's the weather like when Baidu travels to Northern Europe in July?

It's really a good choice to go to northern Europe for the summer in July. Last year, I participated in the Nordic outbound tour of Beijing Youth Travel Service (Holiday Department). At that time, I remember going to Sweden and Norway at the end of June, where the weather was cooler, so I'd better take more thin coats. I remember our tour guide reminded me at that time ~