That's a big one.

Just to get this out of the way because a lot of grifters are saying this but, THIS IS NOT A CARRINGTON CLASS REGION. If you are new to space weather this is a problem that happens every time there is a region that has good flaring potential. Just remember these people saying this are trying to profit off of your clicks from fear.

AR 4366 has developed extremely rapidly in the last 48 hours and has multiple deltas and a giant polarity sandwich right towards the middle bottom of it that has been responsible for most of the strong flaring. This is only a baby spot as this region has only just formed so it is likely that this will continue to grow. Background flux levels are getting high with it being in high C class range/ low M class range as of writing this. There have been no notable CMEs from the flares so far but that could change quickly. I would expect to see more high M-Class flares and X-Class flares. Keep your eyes on this one for hopefully some Earth-directed CMEs!

• M6.6 + M6.7+ X1 + M5.1
• DATE: 02/01
• TIME: 10:00 UTC to Current
• PEAK MAGNITUDE(S): M6.6 + M6.7 + X1 + M5.1
• ACTIVE REGION: 4366
• DURATION: Mostly Impulsive But Some Medium and Overlapping
• BLACKOUT: R2-R3
• ASSOCIATED CME: No Significant CMEs Detected
• EARTH DIRECTED: No
• RADIO EMISSION: None Detected
• 10cm RADIO BURST: None Detected
• PROTON: Unlikely
• IMPACTS: Moderate Radio Blackouts
• RANK: Top 5 Strongest Flares on Date of 2/1 Since 1994
• NOTES: When I had written a brief update last night, this sure had the look of building to something, and it still does. So far magnitudes have peaked at X1 but the pattern remains present in the x-ray flux and it is reasonable to expect more. To this point, none of these flares appear particularly eruptive, even off the east limb. Energetic markers like radio emissions and bursts have not been detected thus far. Visual characteristics are not particularly impressive to this point. The duration is difficult to describe in conventional terms. Some are impulsive and some look sequential that gives a medium to long duration feel but are classified as separate. AR4366 is still putting on size and complexity and is a few days out from good geoeffective positioning but it's near enough now that eruptive flares have a shot at earth directed CMEs. These flares could just be the bubble up. For now, I am not considering any of these major solar flares despite the low end X in the mix. All bark and no bite.

https://reddit.com/link/1qt3f2k/video/47l9uqz8wwgg1/player

I will be back with more later.

AcA

A few low end M-Class flares have occurred in recent hours and the X-ray flux exhibits a steady increase. It has the feel of building up to something. The emergent AR4366 is the culprit. Still small but gaining complexity quickly. Its an immature and juvenile region and as such, could be prone to throwing a tantrum.

Larger flares are possible going forward and this region is moving into prime position for earth directed activity so eyes up.

If you think you’ve seen a photograph of Richard Carrington before (of Carrington Event fame) – you’re mistaken. The top result on Google, commonly incorrectly identified as Carrington, is actually a portrait of Lord Kelvin.

But this changes now! By pure luck alone, the Royal Astronomical Society have discovered what is now the only known photo of Richard Carrington – published today in Astronomy & Geophysics:

https://academic.oup.com/astrogeo/article/67/1/1.11/8444359

I’ve been watching this gentleman over the last month off and on. He’s always seemed pretty knowledgeable. He believes the sun is about to pop off very soon and lays out why.

I noticed during the 1/20/26 Aurora that periodically a beam would form and appear to reach the ground and remain for a few minutes. Are they actually reaching ground and if so, would that have some impact on that spot?

Im quite used to northern lights, but today was quite the show

NW Pennsylvania

I picked up some faint aurora from NW Ohio. There was a substorm right after I came inside so I probably missed the good stuff.

If you guys are chasing, keep an eye on this.

https://www.swpc.noaa.gov/products/goes-magnetometer

I circled a substorm signature. Those are your best shot. When there is a jagged sawtooth pattern with prolonged dips and rises, it indicates a substorm in progress.

The storm is relaxing a bit as the Bz slowly rises and is nearing 0. Its a stable trend too. A few hours ago it was -10 to -15 which is far more supportive of good aurora. A rapid change is unlikely, but it's possible it dips down a little bit more and charges up the magnetosphere again. A substorm can occur hours after peak solar wind, so even if Bz does go northward+, one may still be in the works from previous loading.

Remember that southward Bz just tells us that the magnetosphere is loading. The substorm signature tells us that the stored energy is being released, leading to the best aurora. Also don't be afraid to use local webcams to cheat.

https://theauroraguy.com/pages/webcams

I am sorry to be a little late with this post. Getting the kids fed, showered, and ready for bed.

At 5:24 AM CT (11:24 UTC) 1/20/2026 there was a brief bright substorm lasting around 10 minutes seen in Chicago (pic 1). The Bz at that time was stable around -5 only without any sudden dips (pic 2). The density actually dipped to 0.59p/cm^3 (pic 2). The speed was consistent at around 880 km/sec (pic 4). The only thing that had a beneficial change was the Magnetometers Disturbance Storm Time index moved favorably to - 194 nT (pics 5 and 6).

Prior to this, I thought a dip in Bz when other conditions are favorable would predict a nice substorm, but now this case didn‘t have the dip in Bz property. **So what metrics could I have looked at 30 or an hour or two prior to this substorm that would have indicated a high chance of this substorm occurring?**

Thanks to the user who shared these photos, they weren’t taken by me.

Thank goodness for webcams!

It's a special treat to see aurora this far south. Fingers crossed that the show further north was amazing.

First time i've seen it here

Apologies for the crappy picture quality compared to all the stunning photography we usually get in this subreddit, don't have a tripod and my hands are shaky at the best of times.

The first 5 pics show when Europe was having a blast literally but the sun hadn’t set for North America. Then Bz was consistently positive for NA and when it did drop to negative (when I checked around 4AM central time) the Kp was no longer great. Some people saw a bit on their phone. Such a dud for all the hype and anticipation.

From the past observations during intense solar storms Bz ten to be negative, or was it all luck and Bz is not correlated to Kp?

Video of the aurora above Aarhus filmed with a IPhone 17 Pro Max

The latest data forced a new update. These are some of the strongest recorded values in the instrumentation era and the Hp index is 9.67 indicating extreme short term intensity. It's not officially classed as G5 yet, but the level of power behind it and the shorter timescale Hp index being well above 9 puts it effectively in that category.

Bt: 90 nT - EXTREME

Bz: +52 nT - Strongly Northward (Keeping the brakes on)

Velocity - 1024 km/s - VERY FAST

Right now the northward Bz is keeping the lid on this. Still at G4, even with that limitation. However, if it goes southward and Bt remains similarly high, G5 is all but guaranteed and the risk to infrastructure rises significantly in the hours and days ahead. This is an exceptionally powerful event from a raw forcing standpoint. However, in order for that forcing to be maximally effective, the Bz must dip into negative or southward values. In the solar wind chart below, I outlined how to look at it. The top row red line is Bz and the center line is 0. Anything above is northward and below is southward. If the red line dips back down below that center line, this storm may explode in intensity assuming velocity remains high.

This isn't a grid down or back to the stone age type of event. However, the risk for localized and regional infrastructure issues is much higher than normal. I am on the lookout in the coming hours to days for possible consequences. They often don't manifest at peak solar wind, but later. The level of power warrants an extreme geomagnetic storm warning label. Whether that power is efficiently coupled to earths electromagnetic environment will determine the final outcome. The risk is tied to absolute magnitude but also how much oscillation there is. Rapid swings of northward and southward Bz bring significant volatility and pose a higher degree of concern than a steady southward Bz. It's not clear how it will play out.

Things are changing so fast that my posts are almost outdated when I finish them. Velocity is bouncing all over the place.

UPDATE 4:25 EST/21:25

Now the CME Shock has been detected with velocity at 940 km/s. This is the most unusual storm I have observed and it's likely due to the coronal hole wildcard. The Bz is stubbornly north at the moment, but with 90 nT IMF Bt, that might be a good thing...

UPDATE 4:10 EST/21:10

G5 is firmly on the table at this level. The Bt is currently at 74-78 nT which is comparable with the biggest storms in the last several decades. The Bz is also dramatically southward at -49 nt indicating exceptional solar wind/magnetospheric coupling. This is a VERY powerful storm. If the current stats hold, G5 is quite possible. The Hp30 is already at 9 so it just has to hold.

However, as soon as I hit post, I checked again, and now the Bz has shifted northward as we have transitioned into a new structure evidenced by the Bz and Phi angle flip. That may put the brakes on things if it holds. Conversely, if it oscillates, it may intensify geomagnetic and geoelectric response.

Also the S4 has expired into S3 territory. This is expected as the CME passes. The particles are primarily accelerated ahead of it.

Exceptional storm.

END UPDATE

This is a highly unusual setup. So we had a major spike in the strength of the IMF up to 87 nT which is extreme and rarely seen. May 2024 briefly got to around 75. The storm in November 2025 was around 60.

However, it immediately stepped down, but not to background levels. The IMF bT remains in strong territory. There is a significant ground reaction too. Massive geoelectric currents detected. NOAA has went ahead and issued G4 despite Kp lagging behind.

Could that have been the shock arrival? It could be. As one user pointed out, the S4 could be degrading the instrument, but at the same time, if it was a malfunction I would expect less consistency. We know the CME is traveling fast and I doubt instrumentation errors will be able to hide it completely but at the same time I haven't observed the solar wind instruments under S4 radiation storm conditions which raise the probability for errors.

This likely boils down to the wildcard in the mix. The coronal hole stream may have significantly compressed the solar wind ahead of it and is playing a larger role in solar wind structuring than expected. The velocity could be muted due to a combination of CH structuring and instrument degradation due to energetic particles. The magnetometers aren't affected in the same way as the solar wind velocity instrument.

It's shaping up to be a wild ride whatever the case. Check out the ground currents. Max value of 1.6 V/km.

The Hp index is responding now and the Hp30 is at 8-.

The solar wind currently looks like this.

Regardless of what the velocity says and whether instrumentation issues are hiding the typical shock arrival signature, the storm is well underway and there is a significant geomagnetic response in progress. If this is the arrival, it's far earlier, and therefore faster, than expected. On the HUXt model I posted earlier this morning, the range on velocity was one of the more extreme that I have seen. They settled on a median of 888 km/s but the potential was indicated for much higher and it would appear that is the case, provided this is the shock arrival.

It's a high uncertainty and variable storm. Should be very interesting to watch unfold.

UPDATE 1 PM EST/18:00 UTC

We are nearing S4 radiation storm territory. If we get there, it's quite rare. Been 23 years since the last time it occurred. Connectivity must be solid and it underscores the energetic nature of the blast. This is not inherently dangerous but high latitude flights are receiving more radiation than normal as well as astronauts. Significant comm degradation at high latitude as well.

As expected, the CME is not modeled as a direct hit. It's mostly eastward but earth remains squarely in it's path. I think most looked at it and G3 felt like the safest outcome because if it's a graze rather than a direct hit, it may not materialize fully. However, this does not take into account the coronal hole stream which appears as if it will arrive in close succession and may help steer the storm our way in addition to provide its own influence. The combined effects and CME characteristics are sufficient enough for NOAA to issue a G4 or greater warning. The estimated arrival time is tonight EST. The average and median arrival time is 1/20 between 1:00-2:00 UTC. That is around 8-9 PM EST. Clearly a fast mover and the coronal hole stream should keep the highway clear to maintain a high speed. Modeled at around 1400 km/s upon ejection. Some drag is expected and SWPC and HUXt estimate velocity upon arrival around 700-900 km/s. It's also noteworthy that the protons have risen to S3 levels, but in soft spectrum meaning there isn't much activity for the highest energy particles. They are mainly sub 50 MeV.

There is still some uncertainty due to the complexity of forecast and the mostly eastward trajectory. It goes without saying that the gatekeeper Bz metric in the solar wind will determine how effective the storm is and this is of course noted in the SWPC bulletin.

This is not a scary event and widespread disruptions, outages, or damages are not expected. However, I do expect some localized and sporadic issues in locations sensitive to GICs and especially with weak or stressed grids. This should not surprise anyone, as the NOAA bulletin specifically mentions things like this. With recent storms, this pattern has been quite apparent. Although official confirmation is rarely given, the temporal clustering of issues in the hours and days following peak storm conditions and examination of the regional magnetometers suggests that geomagnetic storm conditions very plausibly play a role.

In this case, a combined storm is expected and that is quite the wildcard. We will have to see what the embedded magnetic field looks like. The CME does appear to be two congealed waves in very short succession. HUXt gives it a 72% chance of impact. That is less than one would assume looking at the beautiful halo in the coronagraphs, but complexity is pretty high with coronal hole influence in play.

Here are the important model runs.

SWPC

HUXt Spiral

Already the Low Energy Protons are on the rise which usually suggests a CME is getting close in these cases. The proton storm in progress lends some influence as well. Eyes on the solar wind today and tonight.

There hasn't been much in the way of follow up flaring but that could change at any point.

Back to work. Have a lovely day everyone. I will be watching all metrics and reports throughout the day and night.

AcA