Date: 2026 Jun 12 1230 UTC
Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
Solar activity remained at low levels. The largest flare of the period was a C5.2 flare from Region 4465 (N09E21, Dhi/beta-gamma) at 12/0214 UTC. Several C-class flares were also observed along the east limb from regions not yet visible on the disk.There are five numbered regions on the visible disk. Region 4465 remains the most active and complex region, although some structural decay was noted with submergence noted in areas outside of its mature primary spot. Region 4464 (S13W22, Dsi/beta) showed notable growth, especially in its southern area. Region 4466 (N06W52, Cro/beta) showed consolidation and subsequent growth of its leading spots following a period of decay. All other regions were stable or in decay.No Earth-directed CMEs were observed in available coronagraph imagery.
Forecast: Solar activity is expected to remain at low levels through 14 June, with a chance for M-class (R1-R2/Minor-Moderate) flaring primarily due to the potential of Regions 4464 and 4465. Activity is anticipated to increase somewhat over the next several days as new regions, recently tracked in Solar Orbiter imagery and indicated by loop structures and limb flares, rotate into view from the east limb.Energetic Particle The greater than 2 MeV electron flux at geosynchronous orbit continued at low to moderate levels, with a peak flux of 498 pfu observed at 11/1400 UTC. The greater than 10 MeV proton flux remained at background levels.
Forecast: The greater than 2 MeV electron flux is expected to remain at low to moderate levels through the remainder of 12 June, before rising to high levels over 13-14 June in response to high-speed stream influences. The greater than 10 MeV proton flux is expected to continue at background levels through 14 June.
Solar wind parameters reflected the ongoing passage of a co-rotating interaction region (CIR) that began around 11/1700 UTC and the subsequent onset of a negative polarity coronal hole high-speed stream (-CH HSS). With these enhancements, total magnetic field strength (Bt) peaked around 15 nT before ending the period around 6 nT. The North-South (Bz) component was predominantly southward, and reached a maximum southward deflection of -13 nT. Solar wind speeds increased from near background and stabilized around 500 km/s by the middle of the period. Coinciding with a drop in density, winds continued to intensify and ended the period around 600 km/s. The phi angle recorded several sporadic sector boundary crossings, but was predominantly in the negative (towards the Sun) orientation.
Forecast: Solar wind enhancements in response to -CH HSS influences are expected to continue through 13 June. Further enhancements are anticipated to begin 13 June and continue into 14 June due to the anticipated arrival of combined effects from CMEs that departed the Sun on 09 and 11 June.
Forecast: Geomagnetic field conditions are likely to reach G1 (Minor) geomagnetic storming levels through the remainder of 12 June under continued -CH HSS effects. G2 (Moderate) geomagnetic storming levels are likely on 13 June due to the persistence of the high-speed stream combined with the anticipated arrival of the 09 June and 11 June CMEs. Conditions are expected to decrease to mostly active levels, with isolated G1 (Minor) storming periods possible on 14 June as CME influences wane.