Summary and Forecast

Solar Summary

(last updated 28 Oct 2025 23:30 UT)

Activity 28 Oct: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 28 Oct: 122/75

Solar Forecast

(last updated 28 Oct 2025 23:30 UT)

29 Oct 30 Oct 31 Oct Activity R0 R0 R0 Fadeouts None expected None expected None expected 10.7cm/SSN 120/72 125/78 130/84 COMMENT: Solar activity on UT day 28-Oct was at the R0 level, with a single C1.7 flare observed at 28/1626UT. There are currently seven numbered sunspot regions visible on the solar disk and two unnumbered regions. AR4266 (N16W22, beta) and AR4267 (N08E02, beta) both showed development over the UT day and AR4267 was responsible for the C1.7 flare at 28/1626UT. An unnumbered region has developed on the disk at around N11W03 with beta magnetic characteristics and an additional unnumbered region has rotated onto the solar disk at around N12E44 with alpha magnetic characteristics. All other regions are either stable or in decay. Solar activity is expected to be at the R0 level over 29-31 Oct. S0 solar radiation conditions were observed on UT day 28-Oct. S0 solar radiation conditions are expected over 29-31 Oct. No Earth-directed CMEs have been observed on UT day 28-Oct. A filament lift off is visible in H-Alpha, SDO and GOES SUVI imagery from 28/0234UT at around N20E40. There is no associated CME visible in available coronagraph imagery. A broad, east directed CME is visible in SOHO coronagraph imagery from 28/1536UT. Coronal dimming over the eastern limb is visible from 28/1521UT in GOES SUVI imagery. This CME is considered a far side event and not geoeffective. The solar wind speed on UT day 28-Oct increased, mostly ranging between 360 to 485 km/s and is currently near 460 km/s. The peak total interplanetary magnetic field strength (IMF, Bt) was 13 nT and the North-South IMF component (Bz) range was -11 to +8 nT. A sustained period of southward Bz (-Bz) began at 28/1600UT and ended at 28/2220UT. It appears the Earth has entered an expected coronal hole high speed wind stream, although the impacts of this wind stream have not yet been as strong as anticipated. The solar wind speed is expected to continue to increase over the 29-30 Oct due to ongoing coronal hole high speed wind effects. A decline is possible on 31-Oct.

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