[Paul R.]

Per NWS: Shock was observed by DSCOVR at 10/0132 UTC. It is believed this shock in the IMF was produced by the 07 Dec CME. Total field reached 16 nT while wind speeds topped out near 571 km/s, producing a period of active geomagnetic conditions. The G3 (Strong) and G2 (Moderate) geomagnetic storming watches for 10 and 11 Dec, respectively, remain in place at this time. However, confidence in storming reaching those levels is diminishing.

NWS' pages on space weather are pretty cool...

[Paul R.]

Oh, links:

https://www.swpc.noaa.gov/news/shock-observed-l1

https://www.swpc.noaa.gov/

https://www.weather.gov/safety/space-ww
(then click on links under “Space Weather Resources”)

I recall events slightly visible as far south as St. Louis or Paducah, KY — NWS mentions one in 2003. But there was a real doozie back in, maybe the late 1970’s? This one was not only visible at the northern horizon: The entire sky at my Mom’s turned red! That was nearly as far south as Cape Girardeau, MO.