Minor C7.4 solar flare erupts at 21:11 UTC on June 27, 2026

A minor C7.4 solar flare erupted at 21:11 UTC on June 27, 2026.

Today’s flares include multiple C-class solar flares across active regions, with notable events such as C2.3 at 06:26 UTC from region 4478, C3.9 at 09:23 UTC from region 4473, C3.1 at 10:53 UTC from region 4475, and C2.9 at 12:21 UTC from region 4479. No M-class or X-class solar flares were reported.

In 24 hours to 12:30 UTC on June 27, solar activity was at low levels. Several active regions produced multiple C-class flares, with the largest being a C5.7 event at 12:48 UTC on June 26. Moderate sunspot region growth was noted, particularly in region 4478, which also exhibited a weak delta magnetic configuration.

Solar activity is expected to continue at low levels from June 27 to June 29, with a chance for M-class flares (R1 – Minor to R2 – Moderate radio blackouts) and a slight chance for X-class flares (R3 – Strong or greater).

Active sunspot regions presently observed on the Earth-facing solar disk include AR 4475 (S09W06 – Beta-Gamma), AR 4476 (N08W29 – Beta), AR 4477 (S13E27 – Beta), AR 4478 (S06E46 – Beta-Gamma-Delta), and AR 4479 (N16E31 – Beta).

Over the past 24 hours, the greater than 2 MeV electron flux reached high levels, with a maximum flux of 1 636 pfu at 17:40 UTC on June 26. The greater than 10 MeV proton flux remained at background levels. The electron flux is expected to remain moderate to high through June 29, while the proton flux should persist at background levels.

Solar wind parameters were slightly elevated due to waning effects from a negative polarity coronal hole high speed stream. The total magnetic field strength averaged around 5 nT, with variable Bz components early, then predominantly northward. Solar wind speed decreased from approximately 650 km/s to about 560 km/s. Solar wind conditions are forecast to normalize as high speed stream effects weaken, with anticipated CME arrival from a June 22 eruption early on June 28, before returning to background conditions by June 29.

Geomagnetic field conditions ranged from quiet to unsettled. Periods of active geomagnetic conditions are likely on June 27 and June 28 due to continuing coronal hole high speed stream influences and anticipated CME impacts. Quiet conditions are expected to return on June 29.