NOAA forecasts geomagnetic storms that could bring aurora visibility to Michigan on Oct. 8-9

The National Oceanic and Atmospheric Administration (NOAA) has issued forecasts for geomagnetic activity that could allow residents of Michigan’s Upper Peninsula and northern areas to see the aurora borealis on Thursday and Friday nights, Oct. 8 and 9. NOAA expects a G1 (minor) storm on Oct. 8 with a Kp index of up to 5, and a G2 (moderate) storm watch for Oct. 9, potentially reaching the same Kp level.

The forecasts are based on a coronal mass ejection linked to an M1.4 solar flare from active region 4549 on Oct. 6, with NOAA noting a continued chance of additional M-class flare activity in the coming days. A Kp index of 5 is generally sufficient for auroral displays at latitudes found in northern Michigan.

Local National Weather Service offices warn that cloud cover could limit visibility in some locations, recommending observers seek out dark-sky sites with clear, dry conditions for the best chance to view the lights.

"G1 (Minor) to G2 (Moderate) geomagnetic storms are likely on 09 Oct with the arrival of a coronal mass ejection that was associated with a M1.4 flare from Active Region 4549 on 06 Oct," NOAA said on its Space Weather Prediction website.

The aurora is produced when charged particles from the solar wind interact with atmospheric gases, causing oxygen to emit greenish-yellow or red light and nitrogen to emit blue hues. The Lansing State Journal contributed to the report.