Your Most Likely Scenario

[Highlander]

Wyoming is closer to the east coast than it is to the west,.. the primary weather patterns are west to east, so if Yellowstone went up, then a lot of the central to western areas of the US would be devastated

This link gives what the `experts` think would happen if the area blew,.. how you would prepare for that I dont know, 6-10 years before its back to normality is a long time

I doubt you could grow outside, not because of ash, but because of the lack of decent daylight, if the power stayed on [ and I dont see why it wouldn't here ],...then its possible you could grow inside under artificial light,

http://www.bbc.co.uk/sn/tvradio/programm...cle2.shtml