Minor C9.5 solar flare erupts at 21:44 UTC on June 28, 2026

A minor C9.5 solar flare erupted at 21:44 UTC on June 28, 2026.

Today’s flares include several events across multiple regions: a C4.1 flare (start 01:44 UTC, end 02:00 UTC, region 4475), a C2.4 flare (start 06:46 UTC, end 07:03 UTC, region 4475), a C2.2 flare (start 07:03 UTC, end 07:09 UTC, region 4475), a C2.7 flare (start 15:01 UTC, end 15:15 UTC, region 4478), a C2.8 flare (start 20:38 UTC, end 20:50 UTC, region 4479), and a C3.3 flare (start 20:50 UTC, end 21:03 UTC, region 4477).

In 24 hours to 12:30 UTC on June 28, solar activity remained at low levels. A long duration C-flare began at 18:09 UTC on June 27, followed by a more impulsive double-peaked C7.4 flare later in the period. A faint coronal mass ejection was observed, with no strong Earth-directed component noted.

Solar activity is expected to remain at low levels from June 28 to June 30, with a chance for M-class flares and a slight chance for X-class flares, primarily from regions 4475, 4478, and 4479.

Active sunspot regions presently observed on the Earth-facing solar disk include AR 4475 (S10W19 – Beta-Gamma), AR 4476 (N08W44 – Alpha), AR 4477 (S15E13 – Beta), AR 4478 (S06E33 – Beta-Gamma-Delta), AR 4479 (N15E16 – Beta), and AR 4480 (S18E07 – Beta).

Over the past 24 hours, the greater than 2 MeV electron flux reached high levels, with a maximum measured at 3 792 pfu. Proton flux above 10 MeV remained at background levels. Electron flux is expected to stay moderate to high from June 28 to June 30, while proton flux remains at background levels.

Solar wind data showed a continued weakening of negative polarity coronal hole high speed stream influences. The total magnetic field ranged from 2 to 4 nT, Bz varied between +/-3 nT, and wind speeds decreased from 555 km/s to 465 km/s. The solar wind environment is expected to return to background levels for most of June 29, with possible enhancement from a CME late on June 29 into June 30.

The geomagnetic field was quiet over the reporting period. Periods of active geomagnetic conditions are possible on June 28 if the anticipated CME from June 24 arrives. Otherwise, mostly quiet conditions are expected through June 29, with unsettled to active levels and isolated G1 – Minor storm conditions likely late on June 29 into June 30 due to a CME from June 26.