Depends upon your definition of the western US. The Pacific states of Washington, Oregon and California will be little affected, as the prevailing weather patterns off the Pacific ocean always are moving from west to east.
If you are talking about west of the Mississippi then you are correct, that new territory should be referred to as Ashland. This area is also the breadbasket for no only the US but much of the civilized world gets it’s corn and other agricultural products from this area.
Here is a map of ash falls from previous Yellowstone eruptions, to give an idea.
Given that we should be leaving the interglacial by now, if past ice core evidence is correct, would a hypothetical Yellowstone eruption be enough of a perturbation to trigger an Ice Age? Also, given that Yellowstone, unlike Toba, is not on the Equator, would the Southern Hemisphere suffer much climatological effects if a new Ice Age wasn’t triggered?
FWIW, I spent today* in YNP. Volcanism seemed moderate throughout.
*Winter snowcoach tours highly recommended - the park is quite beautiful when blanketed with 4 ft of snow. But note that moose and elk are growing notably scarce - they appear unable to withstand predation by wolves.
What the reports say is that they’ve never measured helium release before, so there are no prior measurements to compare it to. They had a model and the actual amount was more than they were expecting. Now they’ve changed the model assuming that the higher rate means there’s a larger magma body under Yellowstone.
They can’t know if there was more or less release in the past, because there are no earlier measurements to compare the new measurements to. So they can’t guess if the magma body has increased or decreased - heated up or cooled.
Check back in thirty or forty years and see what the level has been over a little bit of time. We still won’t know what was happening a thousand years ago, because there were no measurements.
