ALERT: MAJOR TO SEVERE GEOMAGNETIC STORM WARNING
WHEN: 31 MARCH 2022 THROUGH 01 APRIL 2022
(Expected Arrival at Approximately 03:00 UTC on 31 March)
What: A G3-level (or greater) Event likely within 48 hours, triggering aurora (visible and radio), degrading HF (shortwave) communications.
Details:
1. The active sunspot region AR2975 produced a level M 1.0 x-ray flare at 19:20 UTC on UTC date, 28 March 2022. This flare triggered a halo coronal mass ejection (CME) that is expected to overtake and combine with an earlier CME from an M 4.0 x-ray flare which occurred at 11:29 UTC, on 28 March 2022. This combined CME is expected early on 31 March 2022 UTC (i.e., in the evening hours of 30 March 2022, if you are on the east coast of North America). It is highly probable that the passage of the solar plasma cloud, riding on a fast solar wind stream, will produce MAJOR to SEVERE geomagnetic disturbances (a geomagnetic storm).
Expect QUIET to MAJOR geomagnetic activity on 31 March, with a chance of isolated severe storm periods. On 01 April, expect ACTIVE to MINOR geomagnetic storm period. By 02 April, the geomagnetic field should become ACTIVE to QUIET.
2. The arrival and passage of these two (combined) coronal mass ejections are expected to impact the Earth within the next 48 hours, possibly creating visible auroras (Northern and Southern Lights) during local night hours on 30 March through early 01 April (local). The geomagnetic activity level could reach a polar K index of 9, and a Planetary K index (Kp) of 6. If so, aurora could be visible in mid-latitude locations (naked-eye auroras could be visible in North America as far south as geomagnetic latitude 55 degrees, i.e., northern areas of Idaho, Maine, Michigan, Minnesota, Montana, New Hampshire, New York, North Dakota, Washington, Wisconsin, and Vermont) during hours of darkness during the periods of major to severe geomagnetic storm activity.
3. Periods of Radio Aurora Propagation (Au Mode) is likely, creating VHF and HF propagation via E-region ionization clouds. The Four- and Six-Meter bands will likely see aurora mode propagation from early 31 March UTC through 01 April UTC.
Comments: A G3-level geomagnetic storm is classified as a Strong event. This level of geomagnetic activity could require voltage corrections on power systems, and false alarms may be triggered on some protection devices. Intermittent satellite navigation and low-frequency radio navigation problems may occur. Shortwave (HF) radio propagation may be degraded, with the depression of the MUF (Maximum Usable Frequency) over most circuits (the path between a transmitter and receiver, by way of the ionosphere). The HF MUF depressions can be as great as 25%. Polar paths may shut down on HF. Full information on the classification of geomagnetic storm levels: https://www.swpc.noaa.gov/noaa-scales-explanation
Background: Active sunspot region (AR) 2975 produced at least 17 x-ray flares in recent days.
For those interested, here is information of what happens during such an event:
https://svs.gsfc.nasa.gov/20067
https://SunSpotWatch.com
More information will follow as warranted…
Best regards, NW7US