It is because Asheville is situated in a valley between 2 mountain ranges. We can get downsloped and models will show it as at lesser precip amount than surrounding areas. While this modeled minimum has validity, it obviously is not always what happens.
I have seen many snowstorms where that modeled minimum is shown and Avl and the whole French Broad River valley meets or exceeds the surrounding area in snowfall. Of course, I have seen where this minimum has held true.
Asheville has 20 snowstorms historically that have exceeded 10 inches of snow. 65 inches of rain fell at the airport last year. Asheville averages more snow than any non mountain location in the state. It can precipitate here.
So, while the minimum may be correct, I have found it prudent to nowcast. There are plenty of models where the minimum is not that extreme. We shall see.