Solar radiation storm warning issued and canceled after M5.8 solar flare, major X1.1 flare erupts at 20:50 UTC

Key Points:

• The Space Weather Prediction Center (SWPC) issued and quickly canceled an S1 – Minor solar radiation storm warning on June 30 following an M5.8 solar flare from Region 4475 near the Sun’s western limb, which is favorable for solar energetic particles to reach Earth despite no confirmed coronal mass ejection (CME).
• Solar activity remained moderate with multiple C-class flares and an M1.4 flare from Region 4479, which, along with Regions 4475 and 4478, showed complex magnetic configurations and potential for further strong eruptions in the coming days.
• A major X1.1 solar flare erupted from Region 4479 at 20:50 UTC on June 30, causing R3 – Strong radio blackout conditions and Type II and IV radio emissions, indicating a shock in the solar corona; analysis is underway to determine if an Earth-directed CME was produced.
• Geomagnetic activity is expected to escalate to G1 – Minor and possibly G2 – Moderate storm conditions on June 30 and July 1 due to arriving CMEs from June 26-27, with unsettled to active conditions potentially continuing into early July 2 before calming.
• Solar wind conditions returned to near-ambient levels but are forecast to become disturbed with the CME arrivals; radio frequency degradation was expected over Europe, Africa, and the Atlantic at the time of the initial flare.