Answer :

It will affect them because the Great Plains don't have much source of food resources and having a drought can cause emigration and hunger dearh
no water= no crops can be grown
no crops/plants=no animals
no plants/animals= NO FOOD
no plants and animals= loose soil
loose soil= when theres a lot of wind, it can cause a sand storm
why loose soil? well.....plants keeps together the soul, and the soil is hummus-rich. But when theres no dead organisms/plants to fertilize the soil, it gets dry and sand like. wind can move the "sand" which is sandstorms