I understand that it's too early to create a topic about the coronal hole at number 83, because it can disappear in a day, but I thought it would be all right. In short, I couldn't help myself.

So, what do we have? A transequatorial coronal hole of positive polarity. While not as large as CH78 or 80, its positive polarity could play a decisive role in the conditions of the autumnal equinox.

I think that if before the influence begins the solar wind speed drops to values of 300-400, then this will also contribute to the creation of a more disturbed compressed region in front of the CH HSS.

Here are frames of this region of the solar disk over the last 6 revolutions:

Edited September 30Sep 30 by Samrau

Thanks for posting how this CH evolved. Fascinating. Fingers crossed.

2 hours ago, Samrau said:

I understand that it's too early to create a topic about the coronal hole at number 83, because it can disappear in a day, but I thought it would be all right. In short, I couldn't help myself.

So, what do we have? A transequatorial coronal hole of positive polarity. While not as large as CH78 or 80, its positive polarity could play a decisive role in the conditions of the autumnal equinox.

I think that if before the influence begins the solar wind speed drops to values of 300-400, then this will also contribute to the creation of a more disturbed compressed region in front of the CH HSS.

Here are frames of this region of the solar disk over the last 6 revolutions:

Yeah. I was worried when looking at the synoptic map today also. Its “finger” for the lack of a better term seemed to parallel the most active regions on the east limb. Again we probably will need an X to blast pass this intruder. 🤣🤣. Edit Maybe not all bad looking at the Composite AIA on SolarHam again we have what looks like another fountain of flux spray leaving its centre now.

Edited September 29Sep 29 by hamateur 1953
Composite. Removed alliteration. ( woke up 🤣)

I was going to post: "Is there anything to the faint halo CME due 28/29?" last night

Based on tweets from @halocme and other aurora chasers - that a very faint halo CME was due last night. BUT little ions sucked up my time and I just crashed into sleep

Did anyone get anything last night? I really hope so.

From the tweets @spaceweatherwoman retweeted looks like Canada and upper US were able to see the show

2 hours ago, Cations said:

I was going to post: "Is there anything to the faint halo CME due 28/29?" last night

Based on tweets from @halocme and other aurora chasers - that a very faint halo CME was due last night. BUT little ions sucked up my time and I just crashed into sleep

Did anyone get anything last night? I really hope so.

From the tweets @spaceweatherwoman retweeted looks like Canada and upper US were able to see the show

There is a CME on the scoreboard which launched early Sunday, and is expected October 1st. (The scoreboard is not a complete record of all CMEs in my experience. It is just the ones that astronomers are pretty confident will turn up). This might be why your CME is not listed there.

Edited September 29Sep 29 by Stella

4 hours ago, Cations said:

I was going to post: "Is there anything to the faint halo CME due 28/29?" last night

Based on tweets from @halocme and other aurora chasers - that a very faint halo CME was due last night. BUT little ions sucked up my time and I just crashed into sleep

Did anyone get anything last night? I really hope so.

From the tweets @spaceweatherwoman retweeted looks like Canada and upper US were able to see the show

I was out shooting but the aurora was too low (distant) to catch it even in photographs. Katahdin was showing nice colors, bright at times. There was a nice little storm right after midnight. It kept on going like this the whole night and then, bang, right before sunrise there was a very nice substorm that people caught all the way from Illinois and mid-latitudes overall. Only those up at 5:30am EDST saw it. Not me, LOL

This was a Europe/Russia show today. We might pick up some breadcrumbs tonight. I would need to drive probably at least 2h north to get rid of clouds.

2 hours ago, Stella said:

There is a CME on the scoreboard which launched early Sunday, and is expected October 1st. (The scoreboard is not a complete record of all CMEs in my experience. It is just the ones that astronomers are pretty confident will turn up). This might be why your CME is not listed there.

I do not see anything Earth-directed on ENLIL. I guess some of the weak ones are just ignored by the official models?

Coronal holes can take on different shapes and sizes. I would pay more attention to the southern coronal hole, which seems to be number 84, but I can't remember for sure. I believe that its flows will interact with CH83. I hope that this will be highly geoeffective.

@Stella

48 minutes ago, Samrau said:

Coronal holes can take on different shapes and sizes. I would pay more attention to the southern coronal hole, which seems to be number 84, but I can't remember for sure. I believe that its flows will interact with CH83. I hope that this will be highly geoeffective.

@Stella

Indeed, they are CH no. 83 (top) and 84 (bottom) per today's synoptic map. Both have + polarity, which makes me quite hopeful! @Stella

https://www.swpc.noaa.gov/products/solar-synoptic-map

Edited September 30Sep 30 by JessicaF

"I do not see anything Earth-directed on ENLIL. I guess some of the weak ones are just ignored by the official models?"

I think that is definitely the case. I've lost the link now, but another member here had data that was showing a very-unlikely-to-hit-the-Earth CME. it was from the same source that publishes the main CME predictions. This cme didn't appear on that list. So it seems that they do track more of these CMEs, and exclude all those which are unlikely to hit Earth from the main forecast. Unlikely to hit doesn't mean it is impossible, though... which may be why we sometimes get geomagnetic storm conditions unexpectedly?🤔

Edited September 30Sep 30 by Stella

31 minutes ago, Stella said:

"I do not see anything Earth-directed on ENLIL. I guess some of the weak ones are just ignored by the official models?"

I think that is definitely the case. I've lost the link now, but another member here had data that was showing a very-unlikely-to-hit-the-Earth CME. it was from the same source that publishes the main CME predictions. This cme didn't appear on that list. So it seems that they do track more of these CMEs, and exclude all those which are unlikely to hit Earth from the main forecast. Unlikely to hit doesn't mean it is impossible, though... which may be why we sometimes get geomagnetic storm conditions unexpectedly?🤔

Of course! I'm always prepared for any twists and turns! Very often, some people's predictions don't come true, while others do. Even when I make my own prediction, I leave a fraction of a percent for the other outcome. After all, even professional forecasters aren't always accurate. In any case, ignoring some dubious CMEs by professionals isn't catastrophic; a G3 isn't something that could damage any electrical equipment. I think we'll always know about probable G4s and higher in advance. These will be obvious coronal mass ejections, with a wide, dense, full halo.

@Jesterface23 thinks we're already under the influence of CH83\84. I wonder where the thought comes from that there is not much time left before the full transition to HSS? A high solar wind speed that is not hindered by the thin interplanetary medium?

I think the density should still at least increase a little.

1 hour ago, Samrau said:

@Jesterface23 thinks we're already under the influence of CH83\84. I wonder where the thought comes from that there is not much time left before the full transition to HSS? A high solar wind speed that is not hindered by the thin interplanetary medium?

We're hovering around a IMF total strength of 8nT, so there is still a little bit of CIR left. We're bound to fully transition into the HSS at some point within the next day given the timing the CH passed center-disk.

WOW! While I was sleeping, something interesting happened. This is a turn of events. Apparently, this is what was mentioned earlier - the equinox effect!

@JessicaF @Isatsuki San @NightSky @mapguy @StargazingHippy @Joseph French

Guys, please, we already have a theme for this event. Here

I think there will be at least two peaks of aurora activity. Now and later, within the next 30-40 minutes.

Bz has now gone north, but if it comes back south again, and several times, it will be great - the auroras will come one after another.

@Isatsuki San said: "Do you think we will reach G3 or G4 level, since NOAA issued a G3 or even G4 warning? Is this related to the Kiruna substorm?

Or was it due to the prevailing wind current, which was 840 kilometers per second?"

This is related to the equinox effect, a very good example, I've been waiting for this for a long time. You can read about it here.

I think G3 would be the limit for this case. G4 requires more, Bz needs to be in a stronger southern position. And G5 is probably impossible without good CMEs.

@Samrau I do not think we will get pink columns this time. The substorm happened mostly in greens. I know what you mean with the shake up by IMF but as far as I can see, it is not a sufficient shake up to release the energy that just got released gradually. My guess that this is it and it will need hours before the next one. Damn, this looked so promising, we were on the brink but then the stupid Bz could not keep it down and it withered away. I would compare this to something but will not as we should keep this forum pg13.

@Philalethes made an excellent illustration:

Now take a look at the IMF figures:

By - purple

Bz - green/red (if in the south)

Almost ideal conditions were created for the maximum development of the equinox effect.

2 minutes ago, JessicaF said:

@Samrau I do not think we will get pink columns this time. The substorm happened mostly in greens. I know what you mean with the shake up by IMF but as far as I can see, it is not a sufficient shake up to release the energy that just got released gradually. My guess that this is it and it will need hours before the next one. Damn, this looked so promising, we were on the brink but then the stupid Bz could not keep it down and it withered away. I would compare this to something but will not as we should keep this forum pg13.

Geomagnetic storm/substorm and auroras are two different phenomena related to the solar wind. And I know that the level of the former is not equal to the brightness and strength of auroral activities.

The brightness of the polar lights is assessed in points on a special scale from 1 to 4.

Auroral brightness is specified by an International Brightness Coefficient (IBC) or with a light meter (photometer) that measures in units called kiloRayleighs (kR):

IBC (kR) - Description

Zero (0) means subvisual, detected only with instruments.

One (1) is comparable to the Milky Way; whitish with no discernible color.

Two (10) is comparable to moonlit cirrus clouds; color is barely identifiable (usually yellow-green).

Three (100) is like brightly lit cirrus or moonlit cumulus clouds; colors are evident.

Four (1000) is much brighter than three; may cast discernible shadows; good colors, many of them fleeting.

4 hours ago, JessicaF said:

@Samrau I do not think we will get pink columns this time. The substorm happened mostly in greens. I know what you mean with the shake up by IMF but as far as I can see, it is not a sufficient shake up to release the energy that just got released gradually. My guess that this is it and it will need hours before the next one. Damn, this looked so promising, we were on the brink but then the stupid Bz could not keep it down and it withered away. I would compare this to something but will not as we should keep this forum pg13.

Solar wind is currently high and we're in moderate storm conditions, so it seems plausible that we are already in the CIR. Which means it should last a few days longer. Don't give up hope!

It looks like the CIR is just about done now and fully transitioned into the HSS of now just CH 83.

3 minutes ago, Jesterface23 said:

It looks like the CIR is just about done now and fully transitioned into the HSS of now just CH 83.

the temperature is still high.

I would be interested to know how the southern coronal hole 84 might affect 83. Perhaps the solar wind will become more disturbed later?

11 minutes ago, Samrau said:

the temperature is still high.

I would be interested to know how the southern coronal hole 84 might affect 83. Perhaps the solar wind will become more disturbed later?

We pretty much would of gone something along the lines of HSS to CIR/HSS mix to HSS. Old CH 84 does poke up north around half way through, so it is very well possible we could see a little hint of another CIR in 2 or 3 days.

My sky is clear, I'm on duty! It's possible that G1-G2 will happen again soon.

But there's nothing yet.

https://rutube.ru/video/3868e86bcb1196a7e9c1b3866b0a9b72/

the magnetometers have now dropped to K5, but I can't see anything at 54 latitude. At 60 latitude, there were small pillars 15 minutes ago, but they quickly disappeared. I will wait until the power of the hemispheres reaches its maximum or Bz turns north, which will happen soon.

Hemispheric Power 83GW

In 30 minutes (21:40UTC), Bz will turn north, and I hope it starts. The hemisphere's power will reach 92 GW.

There are no Aurors! XD I am going to sleep

1 hour ago, Samrau said:

There are no Aurors! XD I am going to sleep

Do it. Auroras will kick off the moment that you are unconscious 😂

The solar wind speed has now begun to decline relatively rapidly. I don't notice any influence from CH84. CH81 and 82 spoiled our encounter with CH83/84, but they themselves were quite geoeffective. Unless, of course, CH84 CIR begins soon.

Right now, at 6:54 PM, magnetometers are starting to fall.

On 10/2/2025 at 6:52 PM, hamateur 1953 said:

You must be well above my location in Bothell Wa. Edit. Forgot you were in North Bend. Great pinks!

Snoqualmie Pt Park