Easter 2014 Northern Lights – G2 Potential

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The NOAA Space Weather Prediction Center has issued a G2 geomagnetic storm watch for April 20 UTC (8:00PM EST 4/19 – 8:00PM 4/20 EST), and a G1 storm watch continuing into April 21 UTC. This means we may see Kp values in excess of 6 the first day, and above 5 the second day.

Enlil model runs are predicting two waves of geomagnetic activity. The first wave is expected to peak around 5:00am UTC (1:00am EST), the second wave is expected to arrive about 12 hours later. As always, it is difficult to predict the exact time of CME arrival so either of the peaks could be +/- about six hours.

This timing is perfect for Iceland, most of North America, Southern New Zealand, Austrailia and Tazmania, Northern Russia, and the Scandinavian countries. The long duration of the potential event means all of those locations have a good chance of high KP values happening at or near magnetic midnight.

Three Events

There were three Earth-directed Coronal Mass Ejections (CMEs) over the last 3 days. Every CME propagates through space at a different speed. Slower CMEs take longer, typically 3 days, to move from the Sun to Earth. Fast CMEs can arrive in as little as 24 hours.

The first CME contributing to this storm left the Sun late on April 15th. This CME was very slow moving and is likely to arrive at Earth in the first wave of geomagnetic activity. There’s a gap in the satellite data, so we can’t say for sure which sunspot region generated the CME, but it likely came from Active Region 2025.

The second CME is associated with the M1 solar flare late on April 16. This flare was located at Region 2035, classified beta-gamma at the time. The ejecta from this flare was moving faster and is expected to arrive around the same time as the CME from the first event.

Finally, the third, biggest, and fastest moving CME was released from Solar Region 2036 April 18th in association in a long duration M7.3 flare. This CME is moving so fast that is it likely that the matter ejected will catch up with the other two CMEs just before, or just after, all three CMEs pass Earth.

The third CME produced a strong asymmetrical full halo in LASCO imagery. In addition, the EPAM (pictured below – click to enlarge), reacted immediately. You can see the proton density increase almost simultaneously with the M7 flare at noon on the 18th. Following the initial shock, there is a consistent increase in the proton density. This indicates there is a CME moving directly toward Earth. We expect the proton density to continue increasing until the leading edge of the CME arrives at Earth. The higher it gets, the higher we expect Kp values to reach when the CME arrives.

Proton density chart April 19, 2014
EPAM 3-day graph shows an increase in proton density linked to the April 18th CME

Summed up, the geomagnetic events over the next 24 to 48 hours look very promising. Be ready to go out if the KP reaches levels high enough for you see see Aurora.

Happy Hunting!

Three CMEs From Solar Region 2017 Prompt April 2nd Aurora

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As of 8:00pm EST tonight, we have entered the watch period for the G1 Geomagnetic storm watch posted by the Space Weather Prediction Center. The watch runs from midnight April 2nd to midnight April 3rd UTC and means that there is a chance that Global Kp values will increase to minor storm level of Kp=5 during the watch period.

This watch is prompted by three recent CMEs originating from flares at Solar Region 2017 over the weekend. All three CMEs have a chance of producing a glancing geomagnetic blow to Earth.

The biggest of the three flares reached X-Class levels with a measured X-Ray flux of X1.01 on Saturday. This flare produced a Type-II radio sweep with an estimated speed of 4,508 km/s, and a Tenflare of 360 sfu. That is a strong radio sweep and a big Tenflare. The location of the flare was in the northwest portion of the solar disk – specifically at N10W20. You can see the location in the image of the flare below. Due to this location and the orientation of the flare, most of the associated CME will travel to the North of Earth. However, it is a large CME and we expect to see a glancing blow.

x1.01 Solar Flare
X1.01 Solar Flare March 29, 2014.

The other two flares contributing to today’s G1 watch happened 17 and 24 hours earlier. Both were M2 class flares and produced slower moving CMEs. Both of these flares are also directed to the North of Earth. They will arrive at roughly the same time as the faster moving CMEs from the X-Class flare.

The combination of three flares arriving at roughly the same time makes predicting the specific timing of the CME arrival even more difficult than normal. Our favorite CME prediction model, the WSA-Enlil Solar Wind Prediction Model, shows the bulk of the two CMEs arriving between about 1:00am and 10:00am UTC April 2.

Our best guess is that Kp values will stay fairly subdued for this event. We will probably see Kp reaching 4 with a couple short periods at or above 5. Of course, we’d love to see it go higher and get a chance to see some Northern Lights in some of the mid-latitudes. As it stands, areas like Iceland, Greenland, most of Canada, Alaska and eastern Russia will have the best chance for Northern Lights from this storm.

Happy Hunting!