Northern Lights Now – Geomagnetic activity reached G2 storm levels on September 27 bringing stunning views of aurora to high latitude regions. The activity is the result of a coronal hole high speed stream and is expected to continue for the next three days.
Update 07:30 UTC 9/29/2020 03:00 EDT
Geomagnetic activity reached G1 levels occasionally this evening as predicted. Conditions have moderated and the aurora is much less active now. At the beginning of the period, solar wind speed were around 625 km/s. They have since decreased to around 575 km/s. The biggest factor in the decrease in activity is the Bz. Look at how variable it has been over the last 12 hours:
During the period of G2 storming, there was over 4 hours where Bz was sustained south. Any deviation into north (positive on the chart) puts an immediate damper on northern lights activity. The CH HSS is expected to remain geoeffective for the next 24-48 hours, it is very possible we could get another sustained period of south-oriented Bz. Keep an eye on the solar wind data!
Solar wind speeds reached 640 km/s, the highest readings Since the beginning of August. The higher activity is associated with a Northern Hemisphere coronal hole. The coronal hole has a wide longitudinal opening – meaning that it will influence Earth’s magnetosphere for several consecutive days. In addition, the remains of AR 2773, shown below as a brighter area to the left, are just to the East of the CH and have the potential to inject higher wind speeds and density into the stream.
To know exact timing of the expected activity, keep and eye on the solar wind. Generally, the more bars there are on the chart, and the taller they are, the more likely there will be higher KP readings.
Northern Lights Now – Space weather forecasters are predicting a period of G1 and G2 aurora conditions May 15th-17th. NLN is activating the live blog. We’ll aim to update several times a day, or as warranted, so check back often.
NLN Live Blog Update – Saturday, May 18, 04:30 UTC (18:00 EST 5/17)
Live blog time: 52hrs 30min
Calling it. It’s over. This is the last post in this storm’s live blog.
@HaloCME on twitter has offered a compelling explanation as to what happened to this week’s storm. In short, it came early. The G2-G3 storming we saw on Tuesday the 14th was the complex eruption from May 10-11. The follow-on storms arrived on 5/15 as we mentioned in the Thursday, May 16, 05:20 UTC live blog post. Later on the 15th and 16th instability as a result of the pushed the KP as high as KP=3.
The recent G3 storm on May 14 was not just because of CIR followed by HSS, but contributed also by a CME (likely from May 11). Note the periods of depressed proton temperature and smooth field rotation. Looks like another one (from May 13) may be hitting us. pic.twitter.com/c6VGoM4XBT
Thank you as always for following along this storm with NLN. We’ll still be in solar minimum for the next year and a half, but as the G3 storming earlier this week shows, there will still be activity. Please follow NLN on Twitter, Facebook and Instagram.
NLN Live Blog Update – Friday, May 17, 04:30 UTC (00:30 EST 5/17)
Live blog time: 52hrs 30min
Thanks for checking back in. Nothing to report. We are awaiting the third transient. With each hour that passes, it become less likely we will see it.
A quick reminder: take a look at the ways to support NLN. Most don’t cost anything.
NLN Live Blog Update – Friday, May 17, 00:30 UTC (2030 EST 5/16)
Live blog time: 48hrs 30min
Quick update: Nothing to see here.
It’s still been quiet, with a max recorded KP=3. The G2 storm watch is expired, we are now in a G1 storm watch. This is when aurora hunters start guessing the odds that the watch is a dud.
NLN Live Blog Update – Thursday, May 16, 20:30 UTC (16:30 EST 5/16)
Live blog time: 44hrs 30min
Looking at the Bz again there have been two periods of 58 minutes and 60 minutes in the last 6 hours. Individually, these are not enough to produce activity beyond KP=2. They do, however, prime the magnetosphere to react more quickly during the next phase of Bz.
There is no indication yet that the next CME is incoming. Watch and wait.
NLN Live Blog Update – Thursday, May 16, 18:00 UTC (14:00 EST 5/16)
Live blog time: 42hrs 00min
Looks like we had the next CME arrival. Take a look at the 24 and 6 hour solar wind charts. At about 16:40 on the 16th, Bz shifted deeply south, Bt and wind speed showed slight increases. Bz south lasted about an hour, then orientation switched back to the north. Once again, a small impact CME unlikely to cause much aurora.
Some Enlil model runs had the second and third CMEs merging together. While there is a slight chance this aurora event is over, we’ll keep our fingers crossed for the third CME arriving over the next 12 hours.
For hopeful hunters, there is another potential explanation: it’s possible the CME arrival just now was part of the first CME from the complex eruption on May 10 that the Enlil model had merged together. If this is the case, we could see another arrival of the official second CME soon – with the third still waiting for tomorrow.
NLN Live Blog Update – Thursday, May 16, 05:20 UTC (01:30 EST 5/16)
Live blog time: 29hrs 30min
Looking back at the 24 hour solar wind profile (below) it looks like the first CME hit around 18:00 UTC on 5/15. At that time the solar wind speed suddenly becomes more variable, Bt jumps then drops off, and Bz goes from fairly stable to slowly decreasing. This isn’t a classic ICME shock, but it is enough of a change in the background variables that we’ll call it a shift and the indicator of a passing transient.
Bz has been mostly south over the last hour, but it would need to be at -5 for over 45 minutes for there to be much aurora. With the passing of the first CME complete, aurora hunters will need to wait for the next CME expected to arrive later today.
NLN Live Blog Update – Wednesday, May 15, 23:20 UTC (19:20 EST 5/15)
Live blog time: 23hrs 20min
First indication the CME is arriving. Proton density has dropped. We’ll need to wait some more to know the real magnetic structure.
NLN Live Blog Update – Wednesday, May 15, 21:15 UTC (17:15 EST 5/15)
Live blog time: 21hrs 15min
Still waiting for first CME shock.
Let’s talk Moon:
Tonight we have a waxing gbbous Moon. For just about everyone, the Moon will be rising 4:00 and 5:00 in the afternoon and setting between 4am and 5am. It is nearly 80% full and the brightness will work against aurora hunters. There’s not much we can do about this aside from go out between moonset and sunrise or cross our fingers that the aurora is strong enough to see through the moonlight. Drier air will help as it reflects less moonlight.
Over the next three days, Moonset and Moonrise become 45 mins later each night, but the moon continues to get brighter until it is Full on Saturday.
NLN Live Blog Update – Wednesday, May 15, 18:30 UTC (14:30 EST 5/15)
Live blog time: 18 hrs 30min
The expected incoming storm is complex. Many times there is a single flare, or filament eruption that prompts a watch from SWPC. This time there are three separate solar events responsible for the activity. First, A complex combination of a flare and two filament eruptions (7 degrees and 13 degrees) from the interaction between AR2740 and AR 2741 launched CMEs late on May 10 and early on May 11. These CMEs merged and should arrive any moment.
Next Another filament, this time 10 degrees erupted from near center disk around 8pm UTC on 5/12. This CME should arrive in about 24 hours and will likely be the biggest impact we see. Timing is harder to estimate when multiple CMEs are between Earth and Sun so the timing on the second CME has a wider variance than normal (read: don’t worry if it’s late)
Third, another smaller filament happened eruption on May 13. This eruption was slightly more to the west of the second eruption and should give Earth a glancing blow. It is possible that this third CME will merge into the second on and we will only see the second – particularly if the second is slower than forecast and the third is faster.
You can see all of 3 CMEs on the Elil model output below (see: How to Read the Enlil Model ) as curved lenses of activity moving from the Sun towards Earth. The upper plot on the right shows three arrivals as peaks in density.
NLN Live Blog Update – Wednesday, May 15, 16:30 UTC (12:30 EST 5/15)
Live blog time: 16 hrs 30min
Still awaiting the arrival of the first shock. Bt is around 8, Proton density is between 13 and 15 parts per cubic centimeter, and wind speed is steady around 470km/s. Those are all slightly elevated levels. We’ll know the first shock arrives when those each make a sudden shift. For now: Watch and wait.
NLN Live Blog Update – Wednesday, May 15, 04:30 UTC (00:30 EST 5/15)
Live blog time: 4 hrs 30min
If you are wondering whether you are going to be able to see aurora where you live, here’s a handy map. G2 is KP=6. (click to enlarge)
When G2 storming is going on Aurora may be visible across Canada, Central and northern New England, the Great Lakes Region, the Upper Midwest, Alaska, Northern Russia, the Scandinavian Countries, Scotland, and Very Northern Ireland. In the Southern Hemisphere, KP=6 is enough to give the entire South Island of New Zealand a show as well as Tasmania and the South Pole. Of course, you can’t see aurora if the sky is bright, so most of the northernmost spots won’t have a chance due to the midnight sun.
NLN Live Blog Update – Wednesday, May 15, 04:15 UTC (00:15 EST 5/15)
Live blog time: 4 hrs 15min
NLN is expecting at least three separate storm arrivals over the next three days with a chance for a forth. Here are some more details on the expected timings of when there may be G1 and G2 storming. Please note: because this is a complicated forecast, this graphic should be taken with a grain of salt. We could easily see a prolonged period of G2 and some G3, or no G2 at all. We also expect storming to go beyond the end of the three day forecast window.
NLN Live Blog Update – Wednesday, May 15, 04:00 UTC (00:00 EST 5/15)
Live blog time: 4 hrs 0min
SWPC has updated the watches for the anticipated set of storms. There are now G1 watches posted on both 5/15 and 5/17 and a G2 storm watch posted for 5/16.
NLN Live Blog Update – Wednesday, May 15, 00:00 UTC (20:00 EST 5/14)
Live blog time: 0min
Live blog activated. We are expecting this to be a multi-storm several day complex event. Thanks for live blogging with NLN.
Northern Lights Now – Space weather forecasters are predicting a period of G1 and G2 aurora conditions March 23rd and 24th. NLN is activating the live blog. We’ll aim to update a
couple times a day, or as warranted, so check back often.
NLN Live Blog Update – Monday, March 25, 11:30 UTC (07:30 EST 3/25)
Live Blog Time: 43hrs 0mins
Live Blog closed. Thanks y’all! It was wonderful watching this storm and aurora hunting with you.
In the end for forecast wasn’t a total bomb. The CME did arrive, but 36 hours late and far weaker than forecast. The Space Weather Forecasting community will be working together to see how models can be improved, but the short answer is “we need more data.” Space Weather forecasting is where land based meteorology was in the 60s and 70s. It will get better.
This site, the Twitter feed and the FB page all saw record traffic. Your interest and excitement about space weather helps make forecasts better in the long run as it raises awareness of space weather. As we look ahead, we’re expecting some very minor activity as a result of a coronal hole later this week. After that we’ll keep an eye out for new coronal holes and wait for solar minimum to pass. By late 2020 storms like this weekend will be more common again.
Oddly, even though max KP on this storm was just 2, there was a brief period around 6am UTC that yielded some aurora. There must have been a brief and localized disturbance that made this possible. We’ll leave you with these two photos from Isaac from Copper Harbor, MI
NLN Live Blog Update – Monday, March 25, 01:45 UTC (22:45 EST 3/24)
Live Blog Time: 33hrs 15mins
Live blog is now active longer than anticipated. This update: not much to see.
We are still in the ICME wind field. Over the last hour Bz has been variable with a max negative deflection around -5nT. Bz needs to be sustained negative for there to be a chance of KP reaching the 4-5 zone. KP has reflected the activity and reached KP=2.
NLN Live Blog Update – Sunday, March 24, 23:45 UTC (19:45 EST 3/24)
Live Blog Time: 31hrs 15mins
Exciting times! The forecast was not a total bust, we are clearly in the mist of the ICME now. We just saw a second major shift in solar wind data with temperature, By and Phy shifting. During the time between the initial onset and this second shift Earth was in the sheath of the CME. As we enter the next phase, wind speed should now pick up and we may see a change in Bz as we enter the core. Keep your fingers crossed for Bt to increase and Bz to shift into a more favorable orientation.
Because this storm is moving so slowly, we get a nice opportunity to watch it unfold and do analysis in real time. What would take 20 mins in another CME event is taking 40-90 in this one. That also means that if it does shift Bz south for the core of the CME we could have a long duration event which would push KP up to 4-5 and possibly 6.
Here’s the recent shift from ACE data:
NLN Live Blog Update – Sunday, March 24, 21:00 UTC (17:00 EST 3/24)
Live Blog Time: 27hrs 30mins
CME shock arrival is now visible in DSCOVR data.
For aurora hunters, the next thing you are looking for is where Bz will settle and how high the solar wind goes. For there to be any chance at G1 storming, wind speed will need to increase to above 500 km/s and Bz will need to be negative for at least 45 minutes.
Note: There are two bugs on the wind speed page that this storm has helped uncover. Won’t fix until later this week – sorry.
2) Occasionally the proton density bars in the top chart don’t actually display – the data in those charts is refreshed every 2 mins, it’ll come back.
NLN Live Blog Update – Sunday, March 24, 20:45 UTC (16:45 EST 3/24)
Live Blog Time: 27hrs 15mins
Better late than never. The CME arrived! Data from ACE is showing the arrival of the CME with Density, Temp and Wind Speed all jumping. Interestingly, it isn’t showing on DSCOVR data yet. Kudos to anyone who waited it out. We’ll watch for the next 90 mins to see if it will make any aurora, but initial signs show it won’t.
NLN Live Blog Update – Sunday, March 24, 18:00 UTC (14:00 EST 3/24)
Live Blog Time: 24hrs 30mins
This storm refuses to flash the sign that it’s over. As mentioned in the previous update, proton density is still hinting at unusual activity. It has now been above 10 p/cm^3 for over two hours. This makes for the biggest bar yet on the solar wind charts. That chart is designed so that the more bars there are, and the bigger they are, the more likely aurora is.
Still not shutting down the live blog. Tired yet?!
NLN Live Blog Update – Sunday, March 24, 15:15 UTC (11:15 EST 3/24)
Live Blog Time: 22hrs 45mins
For those still following this storm. We are not quite ready to close out this live blog. Notice the proton density – it is slowly creeping up. There’s an outside chance this could still be in advance of the CME shock arrival.
NLN Live Blog Update – Sunday, March 24, 06:15 UTC (02:15 EST 3/24)
Live Blog Time: 13hrs 45mins
Looks like scenario 3 from below.
Of course now that this event is called over, the CME will arrive – just to be fickle. If it does we’ll write about it tomorrow morning. Will wait to close out the live blog to tomorrow as well.
Calling it. Gotta get some sleep.
Still a slight chance the CME arrives in the next 6 hours. It likely missed to the west. Ahh – solar minimum.
Hope you enjoyed the anticipation and, if you went out, the stars and Moon.
NLN Live Blog Update – Sunday, March 24, 05:30 UTC (01:30 EST 3/24)
Live Blog Time: 13hrs 0mins
First hints that there is a change in the solar wind data. Bz has been north for the last 18 hours. In the last 20 minutes, it shifted to a south orientation. It is hard to interpret this in real time or until there is more data. It could mean:
1) There’s just a natural shift in the orientation of the magnetic clouds. The long sustained period of Bz north is an artifact of the slow solar wind so that section of plasma just took a long time to pass. That would mean no aurora.
2) We’re actually in the CME now and it is just FAR weaker than expected. This Bz shift would be as the main body of the CME is passing earth. If this is the case, Bz should slowly continue to shift south over the next several hours. But it won’t become very deep south. Still no aurora.
3) The CME just passed Earth, far to the west. The models missed the placement of the CME or got a bad read on the initial halos from STEREO-A and LASCO. Still no aurora.
4) This is the first hint that we’re about to get hit. If this is the case, the CME shock will probably happen in the next 90 minutes or so. When it does, Proton density and Bt will make sudden shifts, Wind speed will increase and BZ will either dive south or back north. We might get aurora if it dives south.
Hmmm — which are you routing for?
Here’s that Bz shift:
NLN Live Blog Update – Sunday, March 24, 02:00 UTC (22:00 EST 3/23)
Live Blog Time: 9hrs 30mins
Not so much of an update, but wanted to share this thought from @spaceWxMike
Solar wind speed usually doesn’t dip below 300, certainly has occurred but I’m thinking the way to describe this is the CME is causing a traffic jam which is why wind speeds have dipped so low. Remember, any forecast that verifies +/- 12 hours is a great SpaceWx forecast! ?
The idea of there being a traffic jam behind the incoming CME is interesting. This would be like a “calm before the storm” or water receding in advance of tsunami. It’s also like the ripples that form in water streaming down pavement on a hill. If the wind is getting “stopped up” behind the CME, we’ll know it when the CME arrives with a big short spike in wind speed.
Good fodder for optimists tonight.
NLN Live Blog Update – Sunday, March 24, 01:00 UTC (21:00 EST 3/23)
Live Blog Time: 8hrs 30mins
So much hype! NLN is seeing record traffic to our site (thanks y’all), but there is no sign of this storm yet. The later the CME arrives, the lower the wind speed will be when it gets here. At this point, G2 storming is still possible, but unlikely. Without a clear CME shock signal in the solar wind data we’re still at least 90 minutes out from any activity.
On the East coast, the Moon will be coming up in about an hour and a half. Did you know: The moon rises about 40 minutes later every night? It rises at sunset during a full moon. If it rises after sunset but in the evening, you know it is in it’s waning phase. Here’s roughly what tonight’s moon should look like
NLN Live Blog Update – Saturday, March 23, 21:30 UTC (17:30 EST 3/23)
Live Blog Time: 5hrs 0mins
Still nothing yet. Solar wind activity is showing no hint of the arrival of the expected CME. This is the time when aurora hunters start doubting themselves, forecasters, and all the other people out hunting with them. Remember it is always possible that we’ll get nothing – Space Weather Prediction is a new science. That said, it’s too early to call it. Hang tight hunters!
As you await the storm, you can watch the solar wind data. You might want to zoom out to 3 hours or 6 hours. As it approaches, Proton density and Bt will rise. When the CME hits, all four metrics will jump. From that point there’ll still be another 45-90 minutes before we see aurora.
NLN Live Blog Update – Saturday, March 23, 16:30 UTC (12:30 EST 3/23)
Live blog time: 0min
We are activating the live blog. So far there is no activity indicated in solar wind, so we remain in wait and see mode. The initial CME shock was modeled to arrive around noon UTC, so it is a little late but still well within normal +/-. This should be good news for hunters in the Europe, Iceland and North America as it makes it more likely the expected period of G2 will arrive once it’s dark.