Measure the ground rise, time the geysers, get a thermal ground survey from space, compare it to archives.
Whenever our volcanoes in Alaska have dome bulges it means the magma beneath is growing. If this is the case it would be a huge disaster in the making, then we should consider relieving the pressure by other means, even to go as far as drilling holes nearby and detonating nukes to vent the pressure.
Either that or an event a thousand times worse than Krakatoa, literally a near extinction event. An eruption of Yellowstone would decimate the north eastern US, trigger the Madrid Fault in MO, put enough ash in the air to circle the earth many times, it would create an ice age, it could conceivably reverse the magnetic polarity of the poles.
Nothing to lose sleep about, the Messiah will stop it with a snap of his fingers.
It’s George Bush’s fault.
Check the historical ash distributions, and I think you'll find the plume tends more southward. All that heat released should create a low pressure system which would bring in a polar high (cold--very cold this time of year) clear air, wind from the north. For where I live (Western North Dakota) that means a lot of winter, but little or no ash, at least on the first lap around the planet.
New Madrid Fault activity is not a given, we'd notice spring was late (ice age), and who uses a compass anymore anyway? (whacks GPS cussing, 'whaddya mean no signal'?)
OTOH, think of all the jobs hauling ash...