About the activity set for Wednesday-Thursday

[Marcel de Bont]

Let's draw a line in the sand from here on. I hope everyone can keep a friendly tone from here on. This topic is about the expected activity which was expected for Wednesday and Thursday last week and nothing else. We drifted a bit too much to the doom and gloom part of space weather forecasting which is something I want to keep away from in this specific forum.

I think that it is actually worth going into this forecast deeper as the NOAA SWPC was really really wrong with their forecast. These kind of errors should be looked at and learned from.

[Newbie]

I agree with this Marcel, I was really surprised with the report NOAA SWPC put out. To tell the truth I couldn't believe what I was reading. 

Raw data is the best indicator of current conditions. 

 

[Drax Spacex]

On 9/6/2021 at 3:29 AM, Marcel de Bont said:

I think that it is actually worth going into this forecast deeper as the NOAA SWPC was really really wrong with their forecast. These kind of errors should be looked at and learned from.

Perhaps covering all possible bases including the potential for a "stealth CME"?

Have you ever seen a case where the ejecta is Earth-centered in such a narrow cone that it remains in the notched-out center region of LASCO C2/C3, undetected?

I may be grasping at straws here!

[Vancanneyt Sander]

14 minuten geleden, Drax Spacex zei:

Perhaps covering all possible bases including the potential for a "stealth CME"?

Likely, they often make forecasts on the safe side so each prediction has to be taken with a grain of salt. But all forecasts combined by several forecasters based on several model runs was in the range of Kp2 and 5, so not a G2.

The CME did arrive, but way later than predicted. The following is a short summary after the event:

Quote

Actual Shock Arrival Time: 2021-09-03T06:19Z
Arrival characterized by slow magnetic field amplitude rise (reaching only 6.5 nT), accompanied by density/temperature rise, followed by field component rotation, density/tempurature drop, and speed rise. Followed by a SSBC at 2021-09-03T12:12Z, which obscures the later part of the ICME arrival signature.

 

[Marcel de Bont]

True, we space weather enthusiasts aren't really NOAA's customers so it is understandable they are cautious but their G2 watch was really over the top even for them in my opinion. It was very obvious in my eyes that this M4.7 CME would not spark storm conditions. I couldn't even spot the supposed CME of the filament eruption!