It's a little cold then and temp difference is big. The average lowest temp is around 6℃ and the highest is 14℃ this year. If it rains, it will be even colder.
About hotel, you can have a look about these ones:
Crystal Orange Hotel, No. 122, Qing Bo Street, Nan Shan Road, Shang Cheng District;
Flower Inn (West Lake), No. 54, Santai Yunshe, Santaishan Road;
Elan Inn (Wensan), No. 5, Yingye Road, West Lake District