Overnight and continuing into this morning a large space weather event has signaled a G-3 ‘Strong’ geomagnetic storm. On April 22, 2017, I wrote an article titled: Yesterday’s Broad Power Outage Likely Caused By Geomagnetic Storm outlining how the grid failures in San Fransisco, New York, and Los Angeles were likely due to a strong geomagnetic storm. As we know, geomagnetic storms can influence the functioning and reliability of spaceborne and ground-based systems and services or endanger property or human health.
The Planetary K-Index is used to measure geomagnetic storms at Boulder, Fredericksburg, Est. Planetary, and College. The graphs below indicate a strong geomagnetic storm is currently underway and in some locations literally off the chart.
A coronal mass ejection (CME) produced during the early UTC hours of May 23, 2017 hit Earth’s magnetic field at 15:36 UTC on May 27, more than 24 hours after it was expected. Although the solar wind speed is relatively slow, the embedded magnetic field had a prolonged period of southward Bz that managed to spark G3 – Strong geomagnetic storm.
G3 – Strong geomagnetic storm (K-index of 7) threshold was reached at 04:19 UTC. Under G3 conditions, the area of impact is primarily poleward of 50 degrees Geomagnetic Latitude. Power system voltage irregularities are possible and false alarms may be triggered on some protection devices. Spacecraft systems may experience surface charging and increased drag on low Earth-orbit satellites and orientation problems may occur. Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error may occur. HF (high frequency) radio may be intermittent, aurora may be seen as low as Pennsylvania to Iowa to Oregon.
Conclusion: According to Federal Reserve Bank of Atlanta:
"Specifically, people affected by geomagnetic storms may be more inclined to sell stocks on stormy days because they incorrectly attribute their bad mood to negative economic prospects rather than bad environmental conditions."
Could this weekend’s geomagnetic storm lead to stock market losses next week?