By Nidal al-Mughrabi and Fadi Shana DOHA/GAZA (Reuters) -Israel pressed ahead on Saturday with its campaign against Hamas in Gaza’s Khan Younis area, while bad weather hit displaced Palestinians seeking refuge further north in the battered enclave. Residents reported heavy aerial and tank fire across Khan Younis, a part of southern Gaza that has become the focus of Israel’s ground offensive against Hamas, and around two main hospitals there. Hamas said its fighters fired an anti-tank missile at an Israeli tank in southwest Khan Younis. The Israeli military said it killed at least 11 gunmen who…