Yellowstone caldera is approx 45 mi. x 35 mi.= approx. 1500 sq miles.
4 sq miles vs 1500 sq miles= cap gun vs dynamite.
Virtually anything east of Yellowstone to the Mississippi will have ash cover.
That is if it goes off in the same strength as when the caldera was made.
It could just huff and puff a bit.
We have 19 days until a bigger event.......