This map created with satellite data for 11:30 p.m. CDT May 17 shows the extent of the northern auroral oval, one of two permanent caps of aurora centered on Earth’s north and south geomagnetic poles. Normally the oval is small and snugged up over Hudson Bay. Tonight it’s expanded southward and could produce auroras across the northern border of the U.S. Click to see current oval. Credit: NOAA

If it were clear here in Duluth, I’m sure we’d be seeing northern lights. The Kp index, an indicator of magnetic activity around the Earth, shot up to “5″ or minor storm level around 11 p.m. Central time this evening (Friday). From the satellite plot, it appears the auroral oval extends across southern Canada almost to the U.S. border.

Since the aurora is quite high – around 60-200 miles – it’s visible a fair distance to the south of that line. In other words, northern parts of Minnesota, Michigan, Wisconsin, N. Dakota, Montana and Washington may get treated to the sight of northern lights overnight.

Sunspot region 1748 still has the potential for more solar storms. Since the group’s now becoming more face-on to Earth, additional flares could send CMEs in our direction. Another flare on May 17 sent material expected to arrive on the 19th. Credit: NASA

Be sure to take a look at the northern sky tonight for arcs and rays of aurora. As you might guess, the cause for this show lies with the recent X-class flares sunspot region 1748 has been pounding out over the week. Our planet was expected to get a glancing brush from a coronal mass ejection (CME) overnight from one of the recent blasts. Let us know if you see anything. And get ready for May 19 – Sunday – when another blast could spark an even more auroras.