Here in West central Nebraska the only time we didn't get mail for a day or two was after the blizzard of 1949 when the mail was delivered in rural areas by airplane twice a week. Otherwise the mail goes as scheduled. Perhaps in the most rural areas there may be reason to not deliver for several days. We are right at the edge of the Nebraska Sandhills and there are miles of narrow roads and no houses for great distances as most of it is pasture land so it would be bad to get stranded, but I think they deliver as scheduled unless it is absolutely impossible.