Tag Archives: coronal hole

G2 Storm Watch posted for Sept 11

Northern Lights Now – SWPC has posted a G2 storm watch for potential aurora on September 11 with follow-on activity on Sept 12 that may reach G1 storm levels. The image below shows the periods of time to expect the strongest activity. The Red areas should have G2 storming while the orange areas are predicted to have G1 storming.

NLN AuroraCast shows 4 periods over the next two days of G1 or higher activity
NLN AuroraCast shows 4 periods over the next two days of G1 or higher activity

This activity is the result of high speed wind from the second of a pair of coronal holes providing a 1-2 punch. Solar wind speeds reached speeds of 515km/s in the first stream, but the magnetic structure was not favorable to northern lights activity. The second stream, which is already buffeting Earth with wind speeds over 550 km/s is oriented more favorably. Boulder has already registered three periods of G1 storming.

G1 storming has already been recorded at Boulder
G1 storming has already been recorded at Boulder

Happy Hunting

Early September 2018 Aurora Activity

Northern Lights Now – A pair of coronal holes are increasing the chances for aurora early this season. These coronal holes will bring high speed solar wind and the potential for aurora. Stay tuned

The two coronal holes in this image will give earth a 1-2 punch between Sept 6 and 13. Both holes (the dark areas in the image) are located close to the equator which means their wind streams are likely to impact Earth

Two Coronal holes at center disk on Sept 5, 2019
Two Coronal holes at center disk on Sept 5, 2019

So far, based on STEREO-A data, it looks like the second storm may pack a stronger punch.

Happy Hunting

Mid March G1 Storm Watch Posted

Northern Lights Now – Less than a week after the last active period for aurora a new storm watch has been posted by SWPC indicating the potential for G1 storming conditions. The current watch, posted for March 22nd, is due to the anticipated high speed solar wind from a center disk coronal hole.

The current coronal hole is a little further south than the one that brought aurora activity earlier this week and is much closer to center disk. It is smaller than the previous coronal hole, so NLN is forecasting a shorter duration period of activity. Here’s an image of the coronal hole from the SDO satellite.

Southern Hemisphere coronal hole extends northward across the Solar Equator
Southern Hemisphere coronal hole extends northward across the Solar Equator

The initial increase in winds should arrive midday on March 22nd with the KP levels rising soon afterward. Wind velocity should increase from today’s baseline of around 350 km/s to above 500km/s. The best monitor solar wind speed is by keeping an eye on the NLN Solar Wind Dynamics page. The page automatically refreshes with the latest data from DSCOVR every minute.

The timing of the expected activity is shown here on the NLN aurora clock. The period of orange (G1 storming) is expected late in the UTC day.

NLN Aurora Clock shows expected G1 storming late in the UTC day March 22, 2018
NLN Aurora Clock shows expected G1 storming late in the UTC day March 22, 2018

Happy Hunting