by Dave Hennen
CNN Senior Meteorologist
After a slow start the much advertised solar storm that began affecting the earth yesterday morning did reach G3 (strong) levels, on the NOAA scale that measures geomagnetic storms which ranges from G1 (weak) to G5 (Extreme).
NOAA yesterday had backed off their initial predictions that coronal mass ejection that occurred Tuesday evening hurling billions of tons of highly charged particles towards the earth would be strong. The storm, which began hitting the Earth’s magnetic field around 6am ET yesterday was initially weak, but overnight the alignment of the magnetic field associated with the storm began more favorably aligned.
The Earth’s magnetic field points north. If a solar storm arrives with its magnetic field pointing northward, the two fields will repel each other, and the effects are minimized. If however, the storm arrives pointing southward effects are maximized. Lead forecaster of the Space Weather Prediction Center Bob Rutledge says it is a lot like magnets. “It’s like holding two magnets next to each other. If the ends are opposite they snap together, and the same thing happens with the interaction between Earth’s magnetic layer and the geomagnetic storm.” The complicating factor is the orientation can change which is what happened overnight.
Even though the present storm reached the strong level, impacts on Earth have been small. Some flights have been rerouted that would normally fly close to the polls. “The surge in power has been noticeable by power companies, but they are capable of handling it. It would take an extreme high end G5 event to cause major problems” Rutledge said.
Still forecasters say based on overall length and strength this has been the strongest event since November of 2004. Brilliant Auroras were reported overnight from Wisconsin, Michigan, and even into Seattle.
The present solar storm is beginning to diminish, but a new flare occurred overnight from the same area of the sun, and the worst from this latest solar storm is expected to impact Earth early on Sunday morning. Forecasters are saying this could be another strong event, but not as strong as earlier today.