An M4.4 solar flare erupted at 08:48 UTC on April 23 from Active Region 4419 (N15W57), marking the strongest event of the past 24 hours, while Region 4420 (N16E31) expanded in area and developed a beta-gamma-delta magnetic configuration, increasing overall solar activity levels.
Region 4419 produced an earlier M1.6 flare at 04:35 UTC, followed by an M1.2 flare from Region 4420 at 04:59 UTC. Both events generated Type II radio emissions measured at 1 033 km/s and Type IV emissions, and coronagraph imagery from LASCO C2 first detected associated coronal mass ejections (CMEs) near 05:00 UTC on April 23.
The M4.4 flare produced an additional Type II radio emission with an estimated velocity of 722 km/s. Analysis to determine CME trajectory and any Earth-directed component is still in progress as we wait for coronagraph imagery to arrive.
Region 4420 exhibited continued magnetic development and formed a delta configuration, a structure characterized by closely spaced opposite magnetic polarities within a single penumbra. This configuration supports repeated flare production and sustained X-ray output.
The region is approaching the center of the solar disk, placing it in a geoeffective position where any coronal mass ejections produced have an increased potential to propagate along the Sun–Earth line and impact Earth.
Region 4419 is close to the Sun’s west limb, which limits the potential for Earth-directed CMEs.
While Earth-directed CMEs are not likely from this location, it increases the likelihood of solar radiation storms due to improved magnetic connectivity between the eruption site and Earth, allowing energetic particles accelerated during flare and CME activity to propagate efficiently along interplanetary magnetic field lines.
The greater than 2 MeV electron flux at geosynchronous orbit reached high levels over the past 24 hours, with a maximum of 4 920 pfu recorded at 16:05 UTC on April 22, while the greater than 10 MeV proton flux remained at background levels throughout the reporting interval.
Solar wind parameters reflected diminishing influence from a negative polarity coronal hole high-speed stream (CH HSS). The total magnetic field averaged approximately 5 nT, and the Bz component fluctuated between −5 nT and +5 nT. Solar wind speed decreased from approximately 525 km/s to 450 km/s over the course of the period.
Geomagnetic conditions remained mostly quiet, with one isolated unsettled interval recorded. Forecast guidance indicates quiet to unsettled conditions through April 25, with isolated active periods possible as a positive polarity high-speed stream arrives on April 24.
Forecasters expect solar activity to remain at low background levels with a 55% probability of additional M-class flares through April 25, mostly from Regions 4419 and 4420, and potential activity from regions rotating onto the visible disk beyond the east limb.
References:
1 Forecast Discussion – NOAA/SWPC – Issued at 12:30 UTC on April 23, 2026