The National Oceanic and Atmospheric Administration (NOAA) issued a new warning on Friday for an impending G3 geomagnetic storm over the weekend. Solar activity had grown to moderate level, the agency said, with an M1.2 flare from Region 4028, a sunspot region. The storm is expected to light up the northern lights over several regions in the northern hemisphere, covering most of Canada and the United States.
Aurora Forecast and Visibility
A G3 geomagnetic storm can potentially stretch auroras as far south as 45° latitude, potentially reaching locations such as Illinois, Oregon, and southern Germany. Visibility will, however, be highly dependent on local weather, especially clear skies. The NOAA’s Saturday aurora forecast is at Kp: 7 (on a scale of 0 to 9), with the forecast time at 04:28:10.
“The general public can stay updated by checking our webpage for any forecast updates and changes. The aurora can become visible over numerous of the northern states and portions of the lower Midwest to Oregon,” NOAA said.
G2 vs. G3 Geomagnetic Storms
Geomagnetic storms are ranked between G1 to G5. A G2 (Moderate, Kp 6) storm will more likely produce weak power grid jitter, mild disturbance of satellites, and aurorae limited to higher latitudes. But a more intense G3 (Kp 7) storm can cause voltage anomalies, enhanced satellite drag, and aurorae far south.
The NWS Space Weather Prediction Center earlier on Friday had issued a warning for a G2 storm. During the afternoon, NOAA witnessed a solar flare with a radio burst moving at 334 km/s that led to the G3 storm warning.
Past Geomagnetic Storm Events
Intense geomagnetic storms have also lit up the skies in various parts of the globe previously. Last year in October, a powerful storm created a vibrant auroral display in parts of the United States. South Africa’s National Space Agency (SANSA) stated that the phenomenon was caused by a solar flare from sunspot 3842, which exploded on October 3.
Despite the forecast, the strength of geomagnetic storms is variable, either decreasing or increasing in a random manner. Observers have to track real weather patterns and NOAA announcements to track aurora activity.
