9:30 p.m. update: The Space Weather Prediction Center is now saying the most likely scenario is just a glancing blow (G1 minor levels) from the solar storm around 8 a.m on June 9 lasting 24 hours. However, it does still indicate a small (25-30%) chance of a major-severe geomagnetic storm. Note: the state of the art is such that we’ll not know for sure until just 10-12 minutes whether the event will definitely occur - about comparable to the warning time for tornadoes, but the effects if any could be felt worldwide from mid-to-high latitudes in the Northern Hemisphere.

From 5:00 p.m.: The sun unleashed a massive solar storm today in a spectacular eruption that some have called the most impressive yet observed by the NASA’s Solar Dynamics Observatory. The video shown below is dramatic.

The eruption occurs about eight seconds into the video on the bottom right portion of the screen.

NOAA’s Space Weather Prediction Center predicts that the solar flare will generate a coronal mass ejection (CME) - an explosion of charged particles (plasma) spewed into space. This could cause a geomagnetic storm when the plasma reaches and interacts with the Earth’s magnetic field.

However – and fortunately - the angle at which the plasma bombardment reaches the Earth beginning tomorrow and peaking on June 9 suggests the intensity of the geomagnetic storm will reach only G1 (minor) to G2 (moderate) levels on a scale from G1 to G5 (G5 would signify potentially widespread damage to power grids, GPS, and low-earth orbit satellite systems generally).

Note: predicting space weather effects entails considerable uncertainty and, therefore, we advise watching for updates at NOAA and here at CWG.

More video: Wow! This solar event has it all (TheSunToday.com)

Related: Space weather: Are we ready for a solar strike?