There were no radio signatures detected that would suggest a coronal mass ejection (CME) was produced and the location of the source region, now in the SW quadrant of the Sun, does not favor Earth-directed CMEs. However, this is a favorable location for proton storms, and they will remain a possibility before 4298 rotates on the far side of the sun this week.
Radio frequencies were forecast to be most degraded over SE Asia and Australia at the time of the flare.
Solar activity in 24 hours to 00:30 UTC on December 8 was at low levels. Region 4294 (beta-gamma-delta) produced a C7.5 flare at 12:04 UTC on December 7 — the largest of the period. Solar activity increased after the new UTC day started, with M2.4 at 00:12 UTC from Region 4299, M2.0 at 00:36 UTC from Region 4294, the aforementioned X1.1 at 05:01 UTC, and M1.8 at 06:54 UTC from Region 4299.
The M1.8 at 06:54 UTC produced a large CME, and with the source region still in a geoeffective position, an Earth-directed CME is a possibility. Analysis of this event, lasting from 06:40 to 07:04 UTC, is in progress.
Additional M-class flares are likely (65%) through December 10, with a slight chance for X-class flares (15%), given past flare history and the potential of current active regions on the disk.
The greater than 2 MeV electron flux in geosynchronous orbit reached high levels over the past 24 hours, with a peak flux of 1 452 pfu. The greater than 10 MeV proton flux was elevated slightly above background levels.
Looking ahead, the greater than 2 MeV electron flux is expected to reach high levels today and tomorrow, and then decrease to normal to moderate levels on December 10. A slight chance exists for a greater than 10 MeV proton flux enhancement above 10 pfu (S1 – Minor) through December 10 due to the eruptive potential of multiple active regions across the visible disk.
Solar wind parameters reflected the waning influence of a negative polarity coronal hole high speed stream (CH HSS) and possible onset of an anticipated weak transient that left the Sun on December 4. A steady upward trend in total magnetic field strength began after 11:00 UTC on December 7 and peaked around 10 nT at 13:19 UTC on the same day.
The Bz component remained entirely positive. Solar wind speeds decreased from ~550 km/s during that timeframe to ~400 km/s by the day’s end, while phi was primarily oriented in a negative solar sector.
The solar wind environment is expected to remain enhanced today (December 8) due to glancing effects from a CME that left the Sun on December 4.
Further enhancements from a CME produced by the M8.1 flare on December 6 are likely to begin within an arrival window of late on December 8 to midday on December 9.
As a result, the geomagnetic field is likely to reach G1 – Minor geomagnetic storm levels today, followed by G3 – Strong geomagnetic storm levels on December 9. G1 – Minor conditions are forecast for December 10.
References:
1 Forecast Discussion – NOAA/SWPC – Issued at 00:30 UTC on December 8, 2025