Tag Archives: northern lights

G1 Storm Watch Posted for November 8

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Update 0330 GMT – 10:30pm EST

It appears the CME missed Earth, probably to the West and North. It is unlikely at this point there will be any aurora storming tonight.

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Northern Lights Now – The CME from the November 5 filament eruption is now expected to arrive at Earth late on Nov 8 and produce G1 storming. SWPC has issued a G1 geomagnetic storm watch. This forecast is lower confidence and more variable than usual. The current predicted timing shows that the period of KP=5 or higher is likely to happen at the end of the UTC day (or just after sunset on the US East coast and around midnight in Europe)

NLN AuroraCast shows the aurora forecast for potential G1 storming at the end of Nov 8 UTC
NLN AuroraCast shows the aurora forecast for potential G1 storming at the end of Nov 8 UTC

This forecast is low confidence because the majority of the CME is likely to go to the north and west of Earth. If Earth is hit, it will likely be a glancing blow. Further, it is impossible to predict the orientation of the cloud of plasma. If it happens to be oriented with a strong Bz south component, the KP could reach values higher the G1. If it is oriented with a strong positive Bz component, it’s unlikely KP values will read higher than 3 or 4. This is a classic wait-and-see storm.

Here is the WSA-Enlil model output from SWPC. It shows that when the CME arrives, it is likely to have a high proton density. This high proton density, at the same time as increasing solar wind are the primary motivations for issuing the G1 watch (click image for full size):

WSA-Enlil model shows CME arriving midday on Nov 8
WSA-Enlil model shows CME arriving midday on Nov 8

Happy Hunting!

Aurora Live Blog – October 2016 G2 Storm

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Northern Lights Now – There is a 72 hour G2 storm watch in effect from October 24 through October 27, NLN will be live blogging the storm here. Please check back often

Update #10: 0300 UTC 10/29/2016 (midnight EST 10/29/2016)

Earth has been under the influence of that large coronal hole for over 4 days. The last several days have been less exciting than the first day and a half, but over the last 3 hours, activity has picked back up. G1 storming conditions have started up again. Here are the current recorded KP values from Boulder:

On the tail end of this storm, another period of G1 storming is recorded
On the tail end of this storm, another period of G1 storming is recorded

The storming is showing up vibrantly on the Tromso all-sky cam. It’s clear there, the moon is nearly new, and the Aurora is filling the sky!

Exciting full sky of aurora from the Tromso all-sky web cam
Exciting full sky of aurora from the Tromso all-sky web cam

It’s possible this storming could continue several hours. Keep an eye on the KP.

Update #9: 2300 UTC 10/26/2016 (7:00pm EST 10/26/2016)

As evening sets in across the East Coast, the KP drops. KP=4 in the short term forecast. It could go back up any time.

Update #8: 1700 UTC 10/26/2016 (1:00pm EST 10/26/2016)

An two hour period of Bz south from about 14:45 to 16:45UTC pushed storming levels back to G2 (KP=5.67 and above) since the last update. Conditions continue to be favorable for northern lights and will likely to be for the next 12-24 hours at least. Here’s a snapshot of the current recorded KP from boulder, where the most recent period of G2 is visible.

Recorded KP conditions from Boulder as of mid afternoon UTC on October 26
Recorded KP conditions from Boulder as of mid afternoon UTC on October 26

If you are planning on going out tonight, you might want to check out NLN’s handy Last Minute Aurora Viewing Preparation Guide, there are some great tips for what to do before you go out and while you are out. Please bundle up! It’s cold across much of the northern viewing spots and you may be standing still for a long time.

Update #7: 1400 UTC 10/26/2016 (10:00am EST 10/26/2016)

Solar wind speeds have now been elevated for over 24 hours. The big winners from last night’s aurora hunt seem to have been in Europe with some terrific images coming from Denmark.

Here are two time lapse videos from overnight

Update #6: 0345 UTC 10/26/2016 (11:45pm EST 10/25/2016)

Last update for tonight. Solar wind is has exceeded 800 km/s and is in the “very high” range. It does appear that wingKP continues to over estimate the actual KP. There is still enough activity that high latitude clear locations should get a show. Keep an eye on the Bz, if it goes back south for another extended period, there could be a new substorm at any moment.

Solar wind speed has exceeded 800 k/s in the last hour
Solar wind speed has exceeded 800 k/s in the last hour

Seven games is a long series. There is plenty of time left for a comeback.

Update #5: 0200 UTC 10/26/2016 (10:00pm EST 10/25/2016)

Let’s go Cubs! It’s the 6th inning and the Indians are leading 3-0.

The solar storm is continuing. Bz has been variable for most of 10/25 UTC, but there were some periods where there were extended periods with negative Bz. In the spirit of baseball, here’s a random statistic: Of 1440 total minutes in the day, Bz was only negative for 458 of them.

Chicago cubs are in the world series tonight
Chicago cubs are in the world series tonight

Update #4: 2130 UTC 10/25/2016 (5:30pm EST 10/25/2016)

It is now dark in Europe and reports of Northern Lights are rolling in. WingKP predictions have been consistently in the 5.67-7.67 range for the last several hours. It’s important to note that when the wind speed is high and there is a particularly strong ground reading (like the G3 mentioned in the last update) that the wingKP model can overestimate. Even with the overestimate, there is still very strong active storming ongoing now.

About an hour ago, Bz shifted to into a new and solidly southward orientation. It is evident in the graph below starting at about 20:45 UTC. This should give a very nice substorm to Aurora hunters out under the lights for the 45-70 minutes (click the image for full screen).

A consistent period of Bz South should reward aurora hunters over the next hour or so
A consistent period of Bz South should reward aurora hunters over the next hour or so

Here are some Photos from Twitter. Thanks for sharing!

From New Zealand:

Update #3: 1630 UTC 10/25/2016 (12:30pm EST 10/25/2016)

Exciting times! SWPC at Boulder reported a period of G3 storming over the last three hours. Current KP predictions are showing consistently G1-G2 storming. Solar wind conditions are favorable to aurora hunters. Make sure your camera batteries are charged, and check out your cloud cover forecast.

SQPC Boulder reported KP activity levels show G3 storming
SQPC Boulder reported KP activity levels show G3 storming
Strong KP Predicted over the next hour
Strong KP Predicted over the next hour

Update #2: 1300 UTC 10/25/2016 (9:00am EST 10/25/2016)

Solar wind speed has increased to over 600 km/s, and there have been periods of Bz south overnight. The first wave of G1 storming of this storm is predicted in the next 50 minutes or so, with an expected KP of 5.33. There were a couple Twitter reports of Aurora overnight, here’s one from Corinne in Northern Wisconsin

Would you like your photo shared in this live blog? Share it on Twitter and be sure to tag @NorthLightAlert

Update #1: 0300 UTC 10/25/2016 (11:00pm EST 10/24/2016)

One full day into the watch period and the high solar winds are running a little late compared to the forecast. Late on 10/24, winds started to increase to 450 km/s. Over the next 6-8 hours they could increase to as much as 700 km/s. There haven’t been any KP=5 active periods yet, but there has been enough activity for some sporatic reports of aurora in Finland and Iceland to trickle in. Stay tuned, there is likely more to come. Take a moment to appreciate how large this coronal hole has become, in the AIA 211 image in encompasses most of the visible solar disk

Very large coronal hole will bring days of active aurora conditions
Very large coronal hole will bring days of active aurora conditions

Long Duration Aurora Event Expected Through End of October

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Northern Lights Now – A somewhat complicated aurora forecast for G1 storming Oct 22nd and 23rd kicks off what may be a long duration aurora event this week. Let’s break it down and help explain why space weather forecasters think this could be an exciting week.

First, coronal hole on the surface of the Sun rotated into the Earth strike zone on October 19. Coronal holes appear as dark areas when viewing the sun through a 211 angstom filter. This particular hole measures in as “relatively small,” but is still 20 times the size of Earth. As coronal holes rotate with the Sun, they track across the Sun’s surface from East to West or from left to right in most images you see of the Sun from satellites. The area near the center of the visible solar disk is the Earth strike zone, when coronal holes are in that area, they send high speed solar wind towards Earth. It typically arrives at Earth about 3 days later, when any disturbances or ripples in the wind have a higher than usual effect on Earths magnetosphere, prompting the possibility of aurora. Here’s an image of the coronal hole when it was in the Earth strike zone on the 19th.

Small coronal hole pointed toward Earth on October 19
Small coronal hole pointed toward Earth on October 19

Typically the best chances for aurora are at the time the higher solar wind begins, again after it has been high for a long duration, and finally when a disturbance traveling on the wind arrives. When the wind first arrives, it is carrying additional protons that it has “swept up” as it travels from the Sun to Earth. Those particles were moving towards Earth but at a slower speed. When it arrives, it appears as a sharp change in the solar wind data being read from satellites in a pattern know as an “interplanetary shock”. As the storm continues, it has a cumulative effect on the magnetosphere, “pushing it” as though it is a spring. The more compressed that spring is the more sensitive and responsive it is to regular disturbances that constantly emanate from the Sun and travel along the wind stream.

Most of the time those disturbances are small. Their sources can be seen in the normal movement in the Sun’s corona in time lapse video from sites like SDO. Occasionally, there is a larger eruption either from a flare or a filament that adds to this background activity.

On October 20, one of these larger eruptions took place in the form of a filament on the surface of the Sun erupting from an area just north of the coronal hole. The eruption launched a large cloud of plasma and particles, known as a CME or coronal mass ejection, moving toward Earth. It will arrive at Earth while the magnetosphere is still activated from the high speed wind, and so could produce an aurora show. Filament eruptions like this are stunning! This time-lapse of images from SDO shows the filament erupting over a period of about 18 hours, imagine the material flying out into space and towards Earth.

Animated GIF shows time-lapse of SDO images of filament eruption on the Sun on October 20, 2016
Animated GIF shows time-lapse of SDO images of filament eruption on the Sun on October 20, 2016

High solar wind and an arriving CME alone isn’t enough to ensure aurora. The orientation of the plasma cloud has to be just right. As of now, it is impossible to know it’s orientation until the leading edges start arriving at Earth. This means it is difficult to predict the exact timing and duration of the aurora storm. There could be none at all. When it arrives, expect proton density and Bt to increase on the DSCOVR solar wind page. If the Bz goes negative, it means the CME is oriented the right way for aurora if it goes positive or stays positive, there won’t be aurora.

A the tail end of the expected impact from the CME, Earth will fall under the influence of yet another coronal hole. This coronal hole is just rotating into the Earth Strike zone now. This one is much larger. When fully in view it will cover nearly 20% of the solar disk stretching from just south the equator to the Northern Pole of the Sun. This coronal hole has been visible every 27-28 days for the previous three rotations of the Sun. During it’s last rotation it produced 3 days of activity which occasionally reach G2 storming levels. The structure looks similar so it is likely to be equally as strong and have a similar duration. Long term forecasts are predicting there may be KP 5 through the end of the month making this an extremely long period of potential storming. NLN will be continuing to post additional updates on this coronal hole, and any events that happen near it, over the next several posts.

The large coronal hole that produced Aurora on the previous rotation is visible in the North East quadrant of the solar disk
The large coronal hole that produced Aurora on the previous rotation is visible in the North East quadrant of the solar disk

Happy Hunting