BOULDER, Colorado – A moderate to strong geomagnetic solar storm began slamming Earth Tuesday and could last another couple of days, with transformer damage and power grid fluctuations possible, according to NOAA’s Space Weather Prediction Center.
The storm is a G2 “moderate” storm on NOAA’s 5-level space weather scale, although NOAA warned that periods of G3 “strong” activity could occur.
According to the scale, a G2 storm can cause “weak power grid fluctuations” and if it lasts long enough, “transformer damage.” Additionally, “high-latitude power systems may experience voltage alarms.” A G3 storm can mean that “voltage corrections may be required,” with “false alarms triggered on some protection devices.”
In 1859, a geomagnetic storm that would now be categorized as a G5 hit earth, taking out telegraph systems, which were the most advanced technology of the time. NOAA’s space weather scale says a G5 – if it hit Earth – could lead to the “complete collapse” of the power grid.
Under the current storm, auroras may be seen as low as New York to Wisconsin to Washington state.
In July 2012, an 1859-type solar storm known as a coronal mass ejection nearly hit Earth.