Minor C9.3 solar flare erupts at 00:36 UTC on October 13, 2025

A minor C9.3 solar flare erupted at 00:36 UTC on October 13, 2025.

This flare began at 00:17 UTC and ended at 00:51 UTC, originating from region 4246. Today’s flares include a C6.4 event from region 4248 (peak at 00:13 UTC) and a C9.3 event from region 4246 (peak at 00:36 UTC).

In 24 hours to 00:30 UTC on October 13, solar activity was at low levels. The strongest event of the period was a C9.6 flare. Regions 4246 and 4248 continued to show complexity and development, while other active regions were mostly stable or decaying.

Solar activity is likely to remain at low levels with a chance for R1-R2 (Minor-Moderate) radio blackouts from October 13 to 15.

Active sunspot regions presently observed on the Earth-facing solar disk include AR 4245 (S10W0 – Beta), AR 4246 (N24W16 – Beta-Gamma), AR 4247 (S12W52 – Beta), AR 4248 (N06E15 – Beta-Gamma), AR 4250 (N06E20 – Beta), AR 4251 (N19E40 – Alpha), AR 4252 (S13E66 – Alpha), and AR 4253 (S17W10 – Beta).

Over the past 24 hours, the greater than 2 MeV electron flux was at high levels, and the greater than 10 MeV proton flux remained at background levels. The electron flux is expected to continue at high levels, while the proton flux is forecast to remain at background levels from October 13 to 15.

Solar wind parameters reflected a transition from corotating interaction region to high-speed stream, with total magnetic field strength peaking at 16 nT and decreasing to 6–8 nT. Solar wind speeds peaked at approximately 750 km/s during the early UTC day. Enhanced solar wind conditions are expected through October 14 due to ongoing negative polarity high-speed stream influence, with a minor enhancement possible on October 15 from a CME that departed the Sun on October 11.

The geomagnetic field was at active to G1 – Minor geomagnetic storm levels during the past 24 hours. The geomagnetic field is expected to reach active to G1 – Minor storm levels over October 13, become unsettled on October 14, and remain unsettled on October 15 due to potential CME effects.