The Hexi region comprises four prefectures; two are suffering from severe drought, and the other two from floods. Such unusual circumstances, along with Hexi's current situation, allowed Cao Keyuan to perceive a great deal. To be precise, he had already seen many signs since the Hou Clan unified Hexi Province.
The Xiapi County is separated from the Great Jin by an ancient river, and Longxiang County is separated from Hedong by the Tongtian River. From the unique locations of these two places alone, as long as someone is well-informed and quick-witted, they can discern the reasons behind this drought and flooding.
Clearly, this is a form of pressure and intimidation from the major sacred lands of Hedong and the northern Great Jin Dynasty directed at Hexi. There may be other hidden motives, known only to the high ranks of the Hou Clan in Tao City, but the aspect of exerting pressure and intimidation can be nearly confirmed.