Northern Lights Now – A large coronal hole pointed towards earth means there may be many as 72 hours of G2 storming between September 28 and September 30. It is likely that during that time KP values will occasionally be above 5.67 and the aurora borealis will treat Aurora hunters to a show. Refresh this page often as we’ll be posting live updates as this storm impacts Earth.
Update #8: 47:00 hours in, 2300 UTC 9/29/2016 (07:00pm EST 9/29/2016)
Wrapping up the second full day of G2 storm watch, and the third day of active storming. Today there have been 4 periods of G1 storming recorded. There should be more G1-G2 storming over the next 24 hours with the possibility for some G3 if the Bz cooperates (which it hasn’t been doing much of so far this storm.
Update #7: 36:30 hours in, 1230 UTC 9/29/2016 (08:30am EST 9/29/2016)
Since the last update, there has been nearly consistent G1 storming. Pictures of aurora and proton acrs started rolling in on Twitter. Take a look at the 6 hours chart from NLN’s current KP page showing consistently KP5+
These two twitter post show proton arcs that happened overnight for this storm, one in Montana, the other was visible in the North Caithness coast
— Dancing Aspens Photo (@DancingAspens) September 29, 2016
— Karen Munro (@kasmunro) September 28, 2016
Update #6: 29:00 hours in, 0500 UTC 9/29/2016 (01:00am EST 9/29/2016)
Just a quick update. The negative Bz did infact lead to a small substorm. KP is back to G1 levels. Check out that same webcam now, it is showing much more green:
Update #6: 28:15 hours in, 0415 UTC 9/29/2016 (12:15am EST 9/29/2016)
On of the great things about the internet is that people hook up webcams and share them with the world. Check out www.sebeclake.net where you can watch aurora live when it’s cloudy where you are. Right now, it’s clear in Eastern Main and the webcam is showing some faint green on the horizon:
On that note, after it has been quiet for the last 3-4 hours, the Bz has been oriented negative for over 15 minutes now at a strength of more than -5Bz. This means there could be a small substorm coming in the next 30-60 minutes. Watch that KP!
Update #5: 26:00 hours in, 0200 UTC 9/29/2016 (10:00pm EST 9/28/2016)
About one third of the way through the predicted duration of the late September active period and so far the storm is mostly as expected. There have been 2 periods of G2 storming recorded so far and 7 periods of G1. Solar wind has continued to stay in the range of 600-725km/s.
Those strong KP readings are all the more impressive because Bz has been variable, rarely staying negative for more than about an hour. That indicates the long duration of strong solare wind as primed the magnetosphere for a big show if there is a period of negative Bz that lasts a couple hours. Here is the 24 hour view of solar wind data, note that Bz is continuously shifting between negative (south) and positive (south) orientation (click to see full size image):
We have not seen a lot of great pictures from this storm so far. Lots of the traditional Aurora hot spots are clouded in. Hopefully it clears out for some of you over the next 48 hours. Please share your pictures with as at @northLightAlert on Twitter!
Update #4: 20:45 hours in, 2045 UTC 9/28/2016 (5:45pm EST 9/28/2016)
G2 storming is ongoing now!
Update #3: 11:00 hours in, 1100 UTC 9/28/2016 (7:00am EST 9/28/2016)
Activity has decreased a bit over the last 9 hours. One additional period of G1 storming was recorded since the last update, current KP estimates are between 3 and 4 which is not enough for most of our readers to have a chance of seeing a show.
In the lull, let’s take a quick look at NLN’s dynamic inforgraphic of DSCOVR solar wind data. The chart below shows the strength and duration of the wind. Generally, more taller bars mean a better chance of a higher KP. The height of bars indicate how long the solar wind has been favorably exceeded the threshold along the bottom. For example, below: wind speed has been above 400km/s for over 48 hours, above 500km/s for over 18 hours, and above 600 km/s for an hour. One of the most important factors for aurora is Bz, the value on the right of the chart, when it is negative and has been for more than an hour or two, that is some of the best time to go out on the hunt. The chart updates automatically – no need to refresh that page!
Update #2: 3.5 hours in, 0330 UTC 9/28/2016 (11:30pm EST 9/27/2016)
The official G2 watch period has started. There has been G1 and G2 activity consistently over the previous 24 hours, even before the offical watch period begins. This has happened without Bz making a sustained southward shift. Solar wind exceeded 700km/s for about an hour just after midnight GMT. Any sustained period of south oriented Bz could make for a very strong aurora display.
In the 0030 SWPC aurora forecast discussion, there are a pair of notes that it is possible that storming could reach G3 levels over the next three days. This would mean KP values of 6.67 and above!
Update #2: t-2 hours, 2200 UTC (6:00pm EST) 9/27/2016
The storm is rolling! G2 storming levels we reached in the 6:00pm UTC hour. Solar wind speeds are now over 650km/s and there have been periods of south oriented Bz. Here’s the reported 3-hour KP values from SWPC:
Aurora reports are already streaming in! Check out these northern lights that happened just after sunset in Iceland:
— Tyler Collins (@tylerc0llins) September 27, 2016
Update #1: t-20 hours, 0400 UTC (midnight EST) 9/27/2016
SWPC increases duration of storm watch to 72 hours. Here are the updated timings of this G2 storming. It is important to note that these specific timings are less meaningful in a long duration event like this as it’s likely that the exact timing of KP spikes will depend on when substorms carried by the solar wind arrive at Earth.