Volcanologists have been warning for years of the Yellowstone volcano threat.
If Yellowstone erupted into a massive, ash-spewing volcano, how far might the plume travel across the continental United States?
An eruption could blanket the east coast in a few millimeters and bury the Rocky mountains in several meters of ash.
New York and Washington D.C., would get a light dusting of ash measuring roughly one-tenth of an inch, while San Francisco and Seattle would get a heaping 2 inches. Billings, Montana, meanwhile, would have to dig out from a 70-inch pile up.