cme produced by m8.1 solar flare on may 31 2025 sdo soho lasco

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.

m8.1 solar flare may 31 2025 sdo aia 304

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.

aurora borealis by noel bauza

Negative polarity CH HSS triggers G3 – Strong geomagnetic storm

A G3 – Strong geomagnetic storm was observed at 02:16 UTC on May 29, 2025, triggered by the arrival of a negative polarity coronal hole high-speed stream at Earth. Coronal hole high-speed streams, and their associated transition zones called co-rotating interaction regions (CIRs), can create CME-like shock waves that are capable of producing strong geomagnetic disturbances and widespread auroras.