An impulsive solar flare measuring X1.1 erupted from Active Region 3697 at 22:03 UTC on May 31, 2024. The event started at 21:52 and ended at 22:03 UTC.
There were no radio signatures associated with this event that would suggest a coronal mass ejection (CME) was produced.
Radio frequencies were forecast to be most degraded over the United States, Canada, and the Pacific Ocean at the time of the flare.
The region has a ‘beta-gamma-delta’ magnetic configuration and is capable of producing more strong to major eruptions on the Sun.
This was the strongest flare over the past 36 hours. The previous X-class solar flare was a long-duration X1.4 on May 29.
“This is now the 48th X-flare of the current Solar Cycle 25, leaving us just one behind the total amount of X-flares during the entirety of the previous Solar Cycle 24,” said Kevin VE3EN of SolarHam.com.
Region 3697 (previously numbered 3664) exhibited growth in the intermediate spot area and a delta configuration persisted in the leader spot area over the past 36 hours. The region also produced an M1.0 flare at 11:20 UTC on May 31.
C-class flare activity was observed from Regions 3691 (beta-delta), 3697, and 3698 (beta). Region 3691 showed an overall decay trend and magnetic simplification throughout the period.
New Region 3699 (beta) was numbered and exhibited minor growth since emerging.
Region 3698 continued to grow in size and total spot count.
Other activity over the same period included instability along a filament centered near S20E10 at around 08:00 UTC on May 31, but the filament did not lift off.
No Earth-directed CMEs were observed.
Solar activity is expected to continue at moderate to high levels through June 3, with occasional M-class flares and a chance for isolated X-class flare activity.
Solar wind parameters were slightly enhanced over the period. The total field ranged from 1 – 9 nT. Prolonged periods of southward Bz reaching -7 to -9 nT were observed between 00:23 and 05:14 UTC on May 31. Solar wind speed averaged near 350 km/s while the phi angle was variable.
The geomagnetic field was at quiet to unsettled levels, with an isolated period of G1 – Minor geomagnetic storming between 03:00 and 06:00 UTC following a prolonged period of southward Bz and elevated density.
Looking ahead, G1 – Minor to G2 – Moderate geomagnetic storming is likely on June 1 due to flanking effects from the May 29 CME. Quiet to unsettled levels are expected on June 2 and 3.
References:
1 Forecast Discussion – NOAA/SWPC – Issued at 00:30 UTC on May 31, 2024
Featured image: X1.1 solar flare on May 31, 2024. Credit: NASA/SDO AIA 131, Helioviewer, The Watchers
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