The Geophysical Institute at the University of Alaska Fairbanks is predicting a geomagnetic storm for Wednesday and Thursday of this week (July 12th & 13th). Strong northern lights may be visible between 10 PM and 2 AM in parts of the northern US, especially from points of high elevation, clear views of the northern horizon and low light polution.
For those not in the US, is longitude really important when talking about where the northern lights are visible? Most places I’ve seen that they give notices they use US states as references of latitude, but it’s not mentioned if that is really important or you can see them from anywhere in the world, as far as it’s night time and there are no clouds of course
Yeah, totally - the longitude doesn’t really matter, it’s the latitude that’s important. Auroras usually occur between 10 and 20 degrees from the geomagnetic pole. This does bias North America and Greenland a bit, since the geomagnetic pole is shifted toward Canada relative to the geographic north pole. But, if you take a look at the University of Alaska link I posted, they do publish forecast maps for Europe and the north and south poles as well as the US.