Question: In 2007, in which region was this tropical cyclone affecting Oklahoma and Texas formed?
Sentence (from "2007 Midwest flooding"): While Hurricane Dean was affecting the Yucatán Peninsula and the Gulf of Mexico, and Tropical Storm Erin was affecting Oklahoma and Texas, a persistent storm system hung over the Midwest for several days, causing repeated flash flooding in the US states of Illinois, Indiana, Iowa, Minnesota, Ohio, and Wisconsin.
Relevant evidence: Yes