A major "X-class" solar flare exploded on the surface of the sun yesterday, an event which typically results in active and widespread Auroras here on Earth over the next 24-72 hours. These things are always unpredictable, but weather permitting, the lights should be visible throughout Alaska and possibly as far south as the Canadian border or beyond, possibly peaking tomorrow (Friday) or Saturday night, although with a lot of solar activity this past week, it might be worth looking tonight as well.
We've got rain and clouds here in Seattle (what else is new?) so we probably won't get anything, but if you are anywhere north of about 48 degrees, keep your eye on the night sky. Best viewing time is also hard to predict, but tends to be centered on either side of midnight local time. Get away from light pollution, look north...and keep your fingers crossed!
Good luck - and let me know if you see anything. I came home from Canada a few days too soon, I guess!