Last week, the northern half of the US saw its strongest aurora borealis since June, and it appears that the green and purple light show in the sky is back for another round. The National Oceanic and Atmospheric Administration is predicting that an aurora will hit the northern half of the US on the evenings of Nov. 11-12, and it’ll once again reach down to around 21 states. If you missed it due to cloud cover last week, you’ll have a second chance to see it this week. 

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Per NOAA, this week’s aurora will be caused by a G3 geomagnetic storm, which is on the moderate side of the scale. The best time to see it will be the evening of Tuesday, Nov. 11 and the morning of Wednesday, Nov. 12, but it should hang around long enough to give a less impressive, but still largely visible show on the evening of Nov. 12 as well. 

The aurora should be visible in Washington, Idaho, Montana, North and South Dakota, Minnesota, Wisconsin, Michigan and, of course, Alaska. With a high enough viewing point, dark skies and some luck, the aurora may also be visible in Oregon, Wyoming, Nebraska, Iowa, Illinois, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire and Maine. Canada will have the best view overall. 

When it rains, it pours

This aurora comes to Earth courtesy of yet another X-Class solar flare that erupted a couple of days ago. X-Class flares are at the top of the spectrum, making them the strongest. The one causing the aurora on Tuesday and Wednesday is the third such X-Class solar flare to hit Earth, with the other two being the cause of last week’s aurora. NOAA is predicting a Kp 7-level aurora, which the administration calls a «moderate aurora.» 

Much like regular weather here on Earth, these are predictions. The actual aurora may be weaker or stronger depending on how the solar flare interacts with the Earth’s geomagnetic field. There is also a chance that the aurora happening on Nov. 12-13 will be even stronger as another X-Class solar flare was detected in the morning hours of Nov. 11 and is slated to hit Earth on Nov. 12. We’ll update this article if tomorrow’s aurora winds up being projected as stronger.

Aurora viewing tips

Viewing an aurora is pretty straightforward. No matter where you are, you’ll want to drive away from the city and suburbs to somewhere dark in order to get the best view of the aurora. 

If you are along the southern reaches of NOAA’s prediction area, you’ll also want to get up high and point yourself north. You won’t need any instruments to see it, since it’ll be visible to the naked eye. Photographers have also had good luck catching the aurora by taking a picture with a long exposure time, giving the camera ample time to take in the light from the aurora.