Moderate M1.1 solar flare erupts at 14:10 UTC on October 15, 2025

A moderate M1.1 solar flare erupted at 14:10 UTC on October 15, 2025.

Today’s flares include several notable M-class events, with the most intense being an M4.8 flare from region 4246, peaking at 04:15 UTC. Additional significant M-class events included an M3.7 flare (07:18 UTC, region 4246) and numerous minor to moderate C-class flares throughout the period. There is no specific listing for an M1.1 flare at 14:10 UTC in the available event summaries.

In 24 hours to 12:30 UTC on October 15, solar activity remained at moderate levels, driven by multiple M-class flares. The largest flare reached M4.8, with further M-class and C-class activity from regions 4246 and 4248, both of which continue to grow in size and magnetic complexity. Regions 4250 and 4252 remained stable, and other limb regions showed occasional C-class flares.

Minor to moderate (R1-R2) radio blackouts are likely for the next three days, with a slight probability for an isolated R3 (Strong) event due to ongoing and potential flare activity from regions 4246 and 4248.

Active sunspot regions presently observed on the Earth-facing solar disk include AR 4246 (N22W43 – Beta-Gamma-Delta), AR 4248 (N07W13 – Beta-Gamma-Delta), AR 4250 (N07W07 – Beta), AR 4251 (N19E12 – Alpha), AR 4252 (S13E38 – Alpha), and AR 4254 (N10E74 – Alpha).

Over the past 24 hours, the greater than 2 MeV electron flux reached high levels, peaking at 5 130 pfu. The greater than 10 MeV proton flux remained at background levels. The greater than 2 MeV electron flux is expected to return to nominal to moderate levels on October 15 and October 16. There is a slight chance for a greater than 10 MeV proton event above S1 – Minor levels through October 17.

Solar wind parameters were gradually returning to nominal conditions as negative CH HSS effects diminished. The total interplanetary magnetic field remained at or below 6 nT, with a few brief instances of a negative Bz component. The phi angle was predominantly in the negative sector, and wind speeds steadily decreased from 700 km/s to 550 km/s. Solar wind parameters are expected to continue a gradual decline during October 15, with disturbed conditions likely by late on October 15 and persisting through October 17 due to CME arrivals from October 11–13 associated with AR 4246.

Geomagnetic field activity was quiet to unsettled in the past 24 hours. The geomagnetic field will likely remain unsettled to active until late on October 15, when CMEs from October 11–13 may begin impacting Earth’s environment. Moderate storming conditions (G2 – Moderate) are likely on October 16, with G1 – Minor storming expected to continue into October 17.