Aurora May 16 through May 20 Live Blog

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Northern Lights Now – There is an extended period of active aurora predicted for the third week of May 2016. NLN is going into live-blog mode to provide updates as the storm unfolds. Please check this page often.

Some helpful links to us to watch the storms unfold:

  • Live KP: use this to see the KP over the next 45 or so minutes to time your trip outside
  • AuroraCast: NLN’s visualization of the current SWPC 3-day forecast
  • DSCOVR Solar Wind: Raw data that feeds the live KP model – be super science and predict earlier than the models!

NLN Live Blog Update – Sat May 20, 11:30 UTC (03:30 EST)

Thanks for following along the live blog! There may be some residual activity as solar wind is still high, but the storm appears to be over. Here’s a nice timelapse from @isaac_diener of last night’s activity.

NLN Live Blog Update – Sat May 20, 03:15 UTC (23:15 EST)

As anticipated, the third part of this storm is producing the most activity. But it hasn’t been much so far with geomagnetic activity just exceeding the KP=4 level. Solar winds are looking good, so there is still a chance for G1 storming in the next 3-5 hours.

Did you notice the short term KP forecast is behind? Occasionally the source data, which comes from a neural network run by the space weather prediction center goes offline. When it does, predictions come back from the model as -1. Clearly, the level of activity is not negative!

Wing KP model output  is offline - returning an estimated KP of -1
Wing KP model output is offline – returning an estimated KP of -1

When this happens, the best bet is to use the ovation aurora model – which you can find on our page title “Short Term Prediction Down? Use This!

Ovation model at the time of this update shows some activity.
Ovation model at the time of this update shows some activity.

NLN Live Blog Update – Fri May 19, 13:30 UTC (09:30 EST)

Earth is now in the coronal hole high speed wind. Wind speeds are approaching 500km/s. Over the last 45 minutes, Bz has dipped south. If this keeps up, the KP should tick back up.

Bz is now south in part three of this week's activity
Bz is now south in part three of this week’s activity

NLN Live Blog Update – Fri May 19, 01:45 UTC (21:45 EST)

With the start of 5/19 UTC, the G2 storm watch is now in effect as part three of this complex set of storms is expected to arrive. Over the last hour proton density has been steadily increasing. This is an indication that the CIR is about to arrive. It will be followed by high speed winds from the coronal hole. It should be clear in the next 3-5 hours if there will be strong aurora from this storm, of if it is another bust like the first two parts of this week’s activity. Aurora hunters world wide remain optimistic!

Proton density readings steadily rise over the last hour
Proton density readings steadily rise over the last hour

NLN Live Blog Update – Thurs May 18, 12:30 UTC (08:30 EST)

Overnight there was a brief period of northern lights between midnight and 1 am EST while the Bz was oriented southward. Since then, KP has been between 3 and 4. This was long enough for some aurora hunters to capture the show. Here are a couple clips from the NLN Twitter feed. Thanks for sharing!

NLN Live Blog Update – Thurs May 18, 04:15 UTC (00:15 EST)

Finally! Wing Kp model is calling for KP=5.00 shortly. Bz has turned south and persisted for over 2 hours, it has been hovering around -5nT for the last 30 minutes. That is strong enough to make the models predict aurora!

First predicted G1 storm period of this active period - shown on NLN's current KP real-time chart
First predicted G1 storm period of this active period – shown on NLN’s current KP real-time chart

NLN Live Blog Update – Thurs May 18, 01:00 UTC (21:00 EST)

Another quiet day. The maximum measured KP was 2.67. It appears the expected CME went to the South of Earth and we won’t be seeing any impact from it. SWPC updated the watches. They have cancelled the G2 watch for the 17th and downgraded the watch on the 18th to a G1 watch. They did maintain the G2 watch for the 19th and extend a new G1 watch to the 20th.

The third part of the expected storm should start to impact Earth late on the 18th (UTC) as Earth crosses a solar sector boundary and a co-rotating interactive boundary in advance of the wind from the next coronal hole. Then activity should pick up on the 19th as Earth enters the high speed wind from the coronal hole. This is illustrated in the WSA-Enlil (How to read Enlil ) below. Earth is the green filled circle on each of the graphs. At the top, see that density is high as Earth is in the SSBC, on the lower portion, see that wind speeds are picking up as Earth enters the wind stream.

Annotated Frame from WSA_Enlil model shows coronal holes, high speed wind arriving and high density from SSBC
Annotated Frame from WSA_Enlil model shows coronal holes, high speed wind arriving and high density from SSBC

It’s worth checking out the fully animated WSA-Enlil output at SWPC

NLN Live Blog Update – Wed May 17, 11:00 UTC (07:00 EST)

Solar wind speeds have been slowly decreasing overnight as the influence from the first coronal hole wanes. Winds speeds have dropped to around 500km/s. Bz has been oriented southward (negative) for over 2 hours now. The combination what is responsible for pushing short-term Kp predictions to between 3 and 4. Even with the strength of the field low, extended periods of Bz like this can lead to aurora. We aren’t expecting any amazing jumps in Kp until other solar wind parameters become more favorable.

The next feature that may become evident in this storm is the arrival or glancing blow from the CME that launched late on May 13. The material from the CME is slow moving and mostly to the south of Earth. SWPC models are indicating some of the material may have been on the Earth-Sun plane. Here is a snapshot of the CME in lasco C2 and C3 imagery. It is faint, but the CME can be seen as a “cloud” emanating from the bottom right of the Sun at starting around the 21:00 timestamp in C2 (orange/red) and the 22:30 timestamp in C3 (blue)

CME launches late on 5/13 as shown in LASCO C2 imagery from SOHO
CME launches late on 5/13 as shown in LASCO C2 imagery from SOHO
The same CME, but imaged in C3 - zoomed out a little.
The same CME, but imaged in C3 – zoomed out a little.

NLN Live Blog Update – Wed May 17, 03:45 UTC (11:45 EST)

As of midnight, a G2 storm watch is now in effect. SWPC extended the watch an additional 24 hours through May 19. The 19th currently looks like it will be the most active day this week. G1 and G2 storming is predicted for all but one 3-hour period during the that day. Here is the NLN AuroraCast showing the predicted KP for each 3-hour time period over the next three days.

3-day AuroraCast shows very active geomagnetic activity the next three days - particularly on May 19
3-day AuroraCast shows very active geomagnetic activity the next three days – particularly on May 19

For the first day of this event, measured KP peaked at 3.00. Storm levels did not reach the G1 threshold.

NLN Live Blog Update – Tue May 16, 21:00 UTC (17:00 EST)

Despite a G1 storm watch posted for today, it doesn’t appear KP levels will reach 4.67 today. Solar wind speed have increased as a result of the coronal hole high speed stream and have been above 500km/s for most of the day. Solar winds reached a peak speed of 678km/s early in the UTC day, but have since declined. It is not unusual that a predicted G1 storm does not live up to expectations, there is plenty of activity predicted for the next 2 days and probably more. Stay tuned.

Potential for Mid-May Aurora prompts G1 and G2 storm watch

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Northern Lights Now – The large coronal hole that was pointed directly towards Earth on May 12th and 13th combined with recent solar disturbances prompted space weather forecasters to predict there will be an extended period of aurora activity the third week of May. The Space Weather Prediction Center (SWPC) issued storm watches for three consecutive days with a G1 watch posted for May 16, and G2 watches posted for both May 17 and 18. A G1 storm watch means KP values will likely exceed 4.67 during the 24 hour period, a G2 storm watch means the KP will likely exceed 5.67.

SWPC Notifications timeline shows a G1 watch issued for 5/16 and G2 watches on 5/17 and 5/18
SWPC Notifications timeline shows a G1 watch issued for 5/16 and G2 watches on 5/17 and 5/18

The coronal hole responsible for the expected activity stretched from North to South on the solar disk on May 13. In the image below, the coronal hole is the outlined darker area at the time it was directed towards Earth. High speed solar wind exiting from that region should arrive at Earth around May 16. As it arrives, expect solar wind speed readings from DSCOVR to increase, possibly to as high as 600 km/s. As the higher wind pushes on Earth’s magnetosphere, KP will read higher and any aurora will be stronger during periods of negative Bz.

Coronal Hole Faces Earth on May 13, 2017
Coronal Hole Faces Earth on May 13, 2017

After the initial coronal hole impact, there are two additional features that should impact Earth this week. Part two of this storm will be the arrival of a slow moving CME that launched from the southern hemisphere of the Sun on May 13. This CME is visible on LASCO C2 and C3 imagery, but it is faint. There is a decent chance it will miss Earth entirely to the south and we may see nothing from it. But it may also arrive at Earth as a glancing blow. This is a low confidence forecast, but if it does hit there could be G2 storming due the the magnetosphere already being activated by the initial coronal hole. Here’s an animatedGIF of the CME lauching as seen by LASCO C3:

AnimatedGIF of LASCO C3 shows a faint cloud of Plasma lifting off the Sun, mostly to the South
AnimatedGIF of LASCO C3 shows a faint cloud of Plasma lifting off the Sun, mostly to the South

Finally the third portion of this storm is most promising and is expected to impact Earth on 5/19 and 5/20. This second coronal hole produced great activity on the previous rotation in April. NLN will keep you updated with more information about this CH as it’s structure becomes evident.

Please monitor the Northern Lights Now Twitter feed and the live KP charts for updates on when it may be a good time to go out and watch the northern or southern lights dance.

Happy Hunting