PJM issued a geomagnetic disturbance warning, then an action. No emergency actions, and it's already over.
Msg ID: 104606
Message Type: Geomagnetic Disturbance Action
Priority: Action
Effective Start Time: 06.01.2025 09:31
Effective End Time: 06.01.2025 12:25
Regions COMED
A Geomagnetic Disturbance Action has been issued as of 09:31 on 06.01.2025 to protect
the power system from damage or disruptions due to increased geomagnetic activity.
Times are "Eastern Prevailing Time", which is Eastern Daylight Time right now.
Background:
These messages are from the US east coast power grid control room in Valley Forge, PA sending to people at generating stations and other key control centers. This is a slow-moving event. If the grid was stressed, there would be "Pre-Emergency Load Reduction" and "Conservative Operation" actions ordered. If there was real trouble, there would be many more actions. But things never got beyond preparing for trouble.
A geomagnetic disturbance event in 1989 caused transformer damage leading to outages. The solar flux going between power lines and conductive ground induces DC currents into the ground and lines, so that ground potential is different at different points. This causes partial saturation of transformers, and heating. That wasn't noticed until it was too late. So now, DC current in some key AC lines is monitored continuously, so power levels can be reduced if necessary.
Training materials for understanding this:[1] Start at slide 21.
Background info on how a power grid works.[2] Start with "PJM 101"
[1] https://pjm.adobeconnect.com/p63ultsdb2v/
[2] https://www.pjm.com/training/training-resources
> Times are "Eastern Prevailing Time", which is Eastern Daylight Time right now.
I'm trying to recall when I last ever saw "Eastern Prevailing Time" used.
Can anyone share why it's used?
I see more use of ET over that (for Eastern US) or better yet UTC/GMT.
> So now, DC current in some key AC lines is monitored continuously...
Can power lines have multiple currents in them at once? What would that mean for when the AC phase is moving opposite the DC direction?
> https://pjm.adobeconnect.com/p63ultsdb2v/
Apparently my browser does not support some content in the file I'm trying to view and I'm instructed to use, among other things, "Firefox undefined or later". Which may or may not be what I was trying to use to begin with.
Though it seems to work anyway, so okay then.
M8.2 is in the upper medium range (M = M1.0 to M9.9). Next comes X1 which is 10 times stronger than M10. M2 is 10 times stronger than M1.
We might see several of these per year during a solar maximum. So maybe we get some nice auroras.
Edit, TIL: Though the G4 is a different issue, which classifies the impact of a solar flare on our earth. These range from G1 (minor) to G5 (extreme). This means that it can disrupt radio communications and GPS, put stress on power grids and, interestingly, increase satellite drag. G4 storms are rare events and occur only a few times per 11-year solar cycle.
> G4 storms are rare events and occur only a few times per 11-year solar cycle.
Did you mean G5 storms? If I'm reading NOAA correctly, we get about 100 G4 storms per cycle, but only 4 G5 storms per cycle.
https://www.swpc.noaa.gov/noaa-scales-explanation
> interestingly, increase satellite drag.
was reading something about this last week. originally, I assumed that the satellite electronics were getting whacked, but that wasn't the actual reason. these storms can heat the atmosphere causing it to expand/swell during the heating which causes extra drag requiring faster than anticipated use of fuel for station keeping.
just another one of those issues of just how everything in the universe "works together" in the most interesting ways.
I've read there was a huge solar flare in the 19th century that knocked out telegraph equipment all over the world. Do we know how strong that event was on that scale?
I know absolutely nothing about solar weather beyond aurora visuals being a possible outcome depending on where you live. I missed the last chance to see at my latitude (rare) and don't want to miss again.
What could I subscribe to so as to be notified when such events happen?
The Aurora app on iOS can set to send a critical notification when you’re likely to see it in your location.
It alerted me (in New York) this morning at about 4AM — though I slept through it.
It means between an hour and 9 hours from now, we might have a Aurora down to Berlin level at 100%. Now the weather is not the best. More information in 2 hours.
Note that this was published yesterday. The geomagnetic storm is underway right now.
I’ve been using the “My Aurora Forecast & Alerts” app, which is pretty good. I’m using the pro version, but I think the main difference was removing some ads.
On October 10th 2024 there was an x1.8 event and it was basically right at us. First time I’d seen the aurora - happened to be on cape cod at the time where the light pollution isn’t so bad. Was pretty amazing with the naked eye but absolutely incredible in long exposure photos.
My brain tried twice to turn this title into the name of a new nvram device.
M8.2 is also a very old model of Leica M
Hams: How’s the RF propagation with this one?
Hey, m8, it’s a big solar flare!
Good luck to any directional drillers out there trying to drill your well blind.