• Prominence eruption produces large CME off southeast limb

    A large coronal mass ejection (CME) was produced by a prominence eruption off the Sun’s southeast limb at 04:30 UTC on August 20, 2025. The CME is not Earth-directed, and solar activity is forecast to remain at very low to low levels, with a slight chance for M-class flares in the coming days.

  • G4 – Severe geomagnetic storm watch issued for June 2 following strong Earth-directed CME

    The U.S. Space Weather Prediction Center (SWPC) issued a G4 – Severe geomagnetic storm watch for June 2, 2025, following the eruption of a powerful, Earth-directed coronal mass ejection (CME) associated with a long-duration M8.1 solar flare from Active Region 4100. The CME is forecast to arrive at Earth late on June 1, with geomagnetic storm conditions expected to intensify through June 2.

  • Long-duration M8.1 solar flare produces strong Earth-directed CME, impact expected on June 1

    A strong, long-duration solar flare registered as M8.1 erupted from Active Region 4100 at 00:05 UTC on May 31, 2025. The flare began at 23:31 UTC on May 30 and ended at 01:32 UTC on May 31. The eruption produced a significant coronal mass ejection (CME). Model forecasts indicate that the CME is Earth-directed and is expected to arrive on June 1.