A major, long-duration solar flare measuring X1.8 erupted from Active Region 3872 at 07:19 UTC on October 26, 2024. The event started at 05:57 and ended at 07:56 UTC. A large coronal mass ejection (CME) was produced during the event.
A Type IV and Type II (estimated velocity 486 km/s) radio emissions were registered at 06:29 UTC, indicating a strong CME was produced.
In addition, a 10cm Radio Burst lasting 4 minutes and with peak flux of 270 sfu was registered from 06:18 to 06:23 UTC. This burst indicates that the electromagnetic burst associated with a solar flare at the 10cm wavelength was double or greater than the initial 10cm radio background. This can be indicative of significant radio noise in association with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.
Most of the CME is expected to be directed away from Earth, but a part of it may be coming our way.
Radio frequencies were forecast to be most degraded over the Indian Ocean at the time of the flare.
This is the second X-class solar flare since X3.3 at 03:57 UTC on October 24 from Region 3869. Associated with this event were Type II (estimated velocity 601 km/s), Type IV, and Tenflare (5 900 sfu) radio emissions.
Also associated with this large flare was an asymmetric, halo CME that was first visible off the SE limb in SOHO/LASCO C2 imagery at 03:48 UTC on October 24.
Due to the location of the source region, the bulk of the X3.3 CME is expected to be to the south and east of Earth. However, some flanking influence is likely according to modeling efforts. Analysis of several model outputs suggests a possible glancing blow at Earth early to mid-day on April 26.
A G1 – Minor geomagnetic storm watch is in effect for October 26.
Solar activity is likely to be moderate, with a slight chance for X-class flares (10%) through October 28 as more of the magnetically complex area of regions transits further across the SE part of the disk.
Earth-directed CMEs are likely in the days ahead if high activity from these regions continues.
References:
1 Forecast Discussion – NOAA/SWPC – Issued at 00:30 UTC on October 26, 2024