Northern Lights Now – The Space Weather Prediction Center has issued a G1 Geomagnetic storm watch for potential aurora on April 30. This means aurora may be visible for northern latitudes late on the 29th for North American viewers. The predicted display is due to the passing of high speed solar wind from a coronal hole. As of this writing, the period of expected activity is from around mightnight GMT until 9am GMT (or about sunset to early morning on the East Coast of North America). Here is the NLN’s auroraCast:
Northern Lights Now – A large coronal hole was pointed directly towards Earth on April 9th and 10th. The high speed solar wind from that exposed area is should impact Earth on April 13 and 14. Space weather forecasters are expecting two consecutive days of geomagnetic storming. That could bring several opportunities for Aurora hunters to experience the Northern and Southern Lights. Here’s an image from SDO from late on April 9 in AIA 211, a wavelength that makes it easy to see coronal holes:
SWPC is calling for two periods of active Aurora (G1 level storming). The first period is early on April 13 and the second is Early on April 14. For North American Aurora viewers this is in prime evening viewing time. Europeans viewers will have to stay up past midnight. See the NLN Aurora cast for April 13 and 14. The data behind this infographic comes from the Space Weather Prediction Center in Boulder Colorado
Note: It is not an error that both days have the same profile throughout the day. The is what the forecasting models have predicted.
Northern Lights Now – SWPC has upgraded the storm watch posted yesterday from G1 to G2 and extended the watch an additional 24 hours. NLN will be live blogging this storm and sharing updates as they are available – check back often over the next 36 hours for updates.
Tim Peake on the International Space Station:
— Tim Peake (@astro_timpeake) April 3, 2016
Update 3:00 AM UTC 4/3/2016 (11:00pm EST -4/2/2016)
Some lights over Rovaniemi, Finland from All About Lapland:
— All About Lapland (@allaboutlapland) April 3, 2016
In Tasmania, there was a hint of the Southern Lights on the horizon:
— §nÖÖzy (@SussanSays) April 3, 2016
Update 10:00 PM UTC 4/3/2016 (6:00pm EST)
This will be the last post for this period of geomagnetic activity, unless the storm surprises and kicks back up again. In the end this storm was limited to a single period where KP reached the G2 threshold and a second period where it peaked at G1 over a total of nine hours. This isn’t far off from what we originally predicted. The storm arrived about 12 hours later than the preditions. The peak wind speeds meaured was 548km/s, almost exactly as forecast, but the 5 minute average measured speed never passed 520km/s.
There were some people who caught a glimpse of the Aurora, thank you for sharing!
This storm may be wrapping up. Solar wind speeds have already started decreases and are now below 500km/s. KP has also been slowing decreasing after about 4 hours of G1 storming from 18:00 to 22:00 UTC. Once the official data from Boulder is available, we should get confirmation that there was a brief period of G2 storming as well.
The timing and clouds mean not many people got to see aurora during this storm. Astronaughts on the International Space Station should have seen some of the show, and there’s a chance that hunters in New Zealand and possible around the great lakes may have seen some of the show. Please share your pictures with us on Twitter and follow NLN (@northLightAlert) too if you aren’t already.
Update 8:45pm UTC 4/2/2016 (5:45pm EST)
Boulder is reporting one period of G1 storming so far. There has been a brief period where the wing KP was predicting G2 storming (at 6.33 – the peak in the chart below). This storm is coming in just about as expected. It was a little late, which indicates that the solar wind was a little slower than the models, and with the wind a little slower the max KP is a little lower. But the slower wind speed also means the storm could last a little longer than the original forecast. If Bz stays negative there could be an extended period of G1 activity giving North America a show tonight.
Most of the normal aurora hot spots in Europe were clouded in tonight, so there weren’t many northern lights reports. The skies look much clearer over North America tonight. If the storm continues for several more hours (very possible), American and Canadian aurora hunter should be rewarded.
Update 4:00pm UTC 4/2/2016 (1:00pm EST)
The solarstorm is now arriving. Solar wind speeds have increased to above 450 km/s. This storm appears to be arriving with the Bz oriented South. This is great news for aurora hunters. If Bz stays negative (south) over the next several hours, KP shold increase into the G1 and Possbly G2 range.
Update 11:00am UTC 4/2/2016 (7:00am EST)
The expected solar wind has not arrived at Earth yet. In the last hour there have been hints that it may be about to be detected. The Solar Wind Density has increased and is currently registering above 10 parts per cubic centimeter after increasing from the ambient 1-4 p/cm3. This is sometimes a short-term leading indicator that anticipates the increase in wind speed. It is often the case that space weather predictions miss by +/-6 hours, so this is not unexpected.
The delay in the arrival of the expected activity hints that it may be weaker than initially anticipated, but also that it may last longer than initially anticipated. Aurora hunters are now in wait-and-see mode for this storm.
Update 4:00am UTC 4/2/2016 (Midnight EST)
SWPC has upgraded the expected storm from G1 to G2, they are now expecting a period of Moderate storming in the second 3 hour block after the storm arrives. The watch period has also been extended into April 3rd. Here’s the snapshot of the auroracast forecast for today and tomorrow.
Solar wind is still at ambient levels at between 330 and 350 km/s. It should pick up over the next several hours.