That's assuming you can get salt in time for the storm, or even at all at that point. At least on the consumer side, a lot of the manufacturing facilities that produce deicing salt switch over to producing fertilizer around new year's. A year or two ago we had a late winter storm and all of the stores in the area were out, and their warehouses too.
yes, good point. we base our statistical inferences on backward-looking data, but the future can change in ways we're unable to fully predict and account for.
this illustrates that just-in-time isn't an unalloyed good. it trades off resiliency for cost (and a bit of agility). it also introduces more structural variance in the supply chain, exacerbating supply issues, which isn't obvious on first blush (operations research coursework covers this).
