All the astro geeks I hang out with have been buzzing about this for a few days now...
I've seen them as far south as New Mexico a few years back but the Kp index needs to be up around 7.5 or 8 for that to happen.
http://www.swpc.noaa.gov/rt_plots/kp_3d.htmlIf you see something that you "think" might be aurora and are not sure, a good way to tell is that you can see stars through the aurora. If it's just clouds, then you won't see the stars.
Hope someone gets them and gets some good photos!