G3 geomagnetic storm watch for 4 and 5 June

Thursday, 4 June 2026 14:32 UTC

Multiple coronal mass ejections (CMEs) are expected to arrive at Earth in the next 30 hours or so. Yesterday (3 June) there were three CMEs launched which all have possible earth-directed components associated with them. An M9.3 solar flare (full halo), an M7.7 solar flare (partial halo) and an X1.0 solar flare (partial halo) all were eruptive in nature and released ejecta which could arrive late today (4 June) and on 5 June. Sunspot region 4455 being the source of these eruptions which was in an earth-facing position. While these were not the strongest CMEs ever seen, their combined effect might push us to G3 (Kp7) geomagnetic storm levels according to the NOAA SWPC late today (4 June) and tomorrow (5 June).  CME effects should start to wane on 6 June unless more CMEs are launched in the near future.