Rythmic flaring regions in the maximum of solar cycle XXV

After the celebrated active region (AR) 3664, whose flares produced aurorae down to the Mediterranean area on 10-11 May 2024, AR3697 had a rhythmic behavior, which allowed us to predict flares’ timings with accuracy down to the hour in June 2024. Similar behavior was registered in AR4274 and AR4299 in November-December 2025, and again it produced the largest flare of 2025, on 11 November 2025, with geo-effectiveness again reaching locations significantly far from the magnetic poles.
Moreover, these active regions maintained their characteristics (timing and flaring directions) after two whole solar rotations.

An elevated degree of sympatheticity with nearby AR has been also verified: in nearby regions, they triggered other flares or they were excitated to flare, with a connecting time of up to one hour.
Sympathetic flares are usually considered when they are less than 20 minutes apart, but the predictability of such events extended this timescale.

The flaring events of 8 December 2025 with the AR4299 and the nearby giant complex AR4294-96-98 are analyzed in detail, with particular attention given to the sequence M1.1 at 13:05UT in AR4294 and C4.82 in AR4299 at 14:06UT: the propagation of the perturbing wave was visible through the excitation of spotless plages between the two classified ones. These observations were made with the H-alpha telescope.

The cooling phases of the flare X1.95 from AR4299 and M5.05, X1.2 and X5.16, sources of Solar Particle Events (SPEs) from AR 4274 (the same region one rotation before), and the one M9.75 of AR3697 (SPE and Ground Level Enhancement) are also analyzed in X-rays from GOES Satellite data.