Summary and Forecast

Solar Summary

(last updated 16 Sep 2026 23:30 UT)

Activity 16 Sep: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 16 Sep: 100/48

Solar Forecast

(last updated 16 Sep 2026 23:30 UT)

17 Sep 18 Sep 19 Sep Activity R0 R0 R0 Fadeouts None expected None expected None expected 10.7cm/SSN 100/48 100/48 95/41 COMMENT: Solar activity on UT day 16-Sep was R0, with no solar flares. There are currently three numbered sunspot regions on the solar disk, however all regions are stable. Solar activity is expected to be R0 over 17-19 Sep. No CMEs were observed on UT day 16-Sep. S0 solar radiation storm conditions were observed on UT day 16-Sep. S0 solar radiation storm conditions are expected over 17-19 Sep. The solar wind environment on UT day 16-Sep was mildly disturbed at the beginning of the day due to lingering effects from the day before, but returned to background levels over the course of the day. The solar wind speed ranged from 575 to 500 km/s. The peak total interplanetary field strength (IMF, Bt) was 15 nT and the north-south IMF component range (Bz) was +8 to -5 nT. The solar wind may become mildly disturbed early on 17-Sep due to a possible glancing blow from a recent CME, although this is low confidence. Further enhancements are possible due to potential coronal hole connections, although it is becoming less likely they are able to connect with Earth.

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