Summary and Forecast

Solar Summary

(last updated 12 Sep 2026 23:30 UT)

Activity 12 Sep: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 12 Sep: 109/59

Solar Forecast

(last updated 12 Sep 2026 23:30 UT)

13 Sep 14 Sep 15 Sep Activity R0 R0 R0 Fadeouts None expected None expected None expected 10.7cm/SSN 105/54 105/54 100/48 COMMENT: Solar flare activity on UT day 12-Sep was R0, with no solar flares. There are currently seven numbered sunspot regions on the solar disk, however all regions are currently stable with little potential for flaring. Solar flare activity is expected to be mostly R0 over 13-15 Sep. On UT day 12-Sep a slow moving CME was observed directed to the southwest, however it is likely too slow to affect the Earth. S0 solar radiation storm conditions were observed on UT day 12-Sep. S0 solar radiation storm conditions are expected over 13-15 Sep. The solar wind environment on UT day 12-Sep was mostly undisturbed. The solar wind speed ranged from 430 to 400 km/s. The peak total interplanetary field strength (IMF, Bt) was 8 nT and the north-south IMF component range (Bz) was +6 to -6 nT. The solar wind is expected to remain mostly at background levels on 13-Sep, but may become enhanced due to connection with a coronal hole on 14-Sep or early 13-Sep with effects going into 15-Sep. A second coronal hole is expected to connect with the Earth either late 14-Sep or else on 15-Sep.

Solar Activity levels are explained in the SWS Solar Terrestrial Glossary.