Analysis and modeling of the first CME indicated an Earth-directed event with arrival at Earth by 17:00 UTC on December 31, according to NOAA Space Weather Prediction Center (SWPC).
Additionally, AR 3939 produced an M3.3 flare at 17:08 UTC that resulted in yet another partial-halo CME, although a more faint, first seen in NASA coronagraph imagery around 18:00 UTC. The second impact is expected at around 06:00 UTC on January 1, 2025.
As a result, a G3 – Strong Geomagnetic Storm Watch is in effect for December 31. However, this Watch does not take into account the second, weaker, CME impact so we might see periods of even stronger geomagnetic storming.
During G3 – Strong geomagnetic storms, voltage corrections may be necessary to maintain stability in power systems, and some protection devices may trigger false alarms. For spacecraft operations, the storm can cause surface charging on satellite components, increased drag on low-Earth-orbit satellites, and potential orientation issues requiring corrective measures.
Other systems can also experience disruptions, such as intermittent satellite navigation and low-frequency radio navigation problems, as well as irregularities in high-frequency (HF) radio communication.
Additionally, auroras associated with G3 storms have been observed at latitudes as low as Illinois and Oregon (around 50° geomagnetic latitude).
G3 storms occur approximately 200 times per solar cycle (11 years), or about 130 days per cycle.
SWPC said confidence is moderate to high in geomagnetic storming outcome, but exact storm strength and timing are lower due to the nature of the filament eruption.
Increased solar activity since December 29 — Three X- and over 20 M-class flares
Solar activity has been at high levels since early December 29 (UTC), with over 20 M- and 3 X-class solar flares in just over 24 hours.
The activity increased notably with M1.0 flare at 02:35 UTC on December 29, with eight M-class flares produced before a major X1.1 flare from AR 3936 at 07:18 UTC on December 29.
Before the end of the UTC day, our star produced a total of 21 M-class flares, leading up to two more X-class flares on December 30.
A major solar flare measuring X1.5 erupted from Active Region (AR) 3936 at 04:14 UTC on December 30. The event started at 04:01 and ended at 04:28 UTC. The flare was associated with a 10cm Radio Burst (tenflare) from 04:08 to 04:15 UTC, with a peak flux of 1 000 sfu.
This event was followed by an impulsive X1.1 flare, which started at 04:29 and peaked at 04:31 UTC. This major event ended at 04:34 UTC and was produced by AR 3932. A tenflare lasting 2 minutes with a peak flux of 430 sfu was registered from 04:29 to 04:31 UTC.
A 10cm radio 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 indicate significant radio noise associated with a solar flare. This noise is generally short-lived but can cause interference for sensitive receivers including radar, GPS, and satellite communications.
Solar activity forecast
3929 – Beta
3932 – Beta-Gamma
3933 – Beta-Gamma
3935 – Alpha
3936 – Beta-Gamma-Delta
3937 – Alpha
3938 – Beta-Gamma
3939 – Beta
3941 – Beta-Gamma
3942 – Alpha
Solar Synoptic Map for December 30, 2024. Image credit: SWPC
There are currently 11 active sunspot regions on the Earth side of the Sun. Four of them have ‘Beta-Gamma’ magnetic configuration and one has ‘Beta-Gamma-Delta’ — all are capable of producing strong to major eruptions on the Sun.
Solar activity is expected to continue at moderate to high levels over the next three days, with a 75 – 80% chance for M-class solar flares and 25 – 30% for X-class as the conglomeration of regions approaches the Sun’s western limb.
SDO outage notice: JSOC is offline
Unfortunately, we don’t have high-quality Solar Dynamics Observatory (SDO) images of these events—or any SDO images at all—since November 26, due to a major flood in the Joint Science Operations Center (JSOC) server room caused by a chilled-water pipe break.
The flooding caused extensive water damage to the lab housing the machines that process and distribute data from the Helioseismic and Magnetic Imager (HMI), Atmospheric Imaging Array (AIA), and the IRIS spacecraft.
As a result, science data processing for these instruments has been severely disrupted, and access to archived data at JSOC is currently unavailable. The Stanford JSOC team is actively assessing the damage and planning recovery efforts, but restoration is expected to take a significant amount of time.
References:
1 Forecast Discussion – NOAA/SWPC – Issued at 00:30 UTC on December 30, 2024
2 Major X1.1 solar flare erupts from Region 3936, CME impact possible on December 31 – The Watchers – December 29, 2024
3 Solar activity ramps up with three X-class and over 20 M-class solar flares in 24 hours – The Watchers – December 30, 2024
4 Outage at the Stanford, JSOC is Offline – NASA/SDO – Accessed December 30, 2024