Summary and Forecast

Solar Summary

(last updated 29 May 2026 23:30 UT)

Activity 29 May: R1 Flares Max Fadeout Freq. Sectors M1.1 0705UT possible lower Mid East/Indian Observed 10.7 cm flux/Equivalent Sunspot Number for 29 May: 148/102

Solar Forecast

(last updated 29 May 2026 23:30 UT)

30 May 31 May 01 Jun Activity R0-R1 R0-R1 R0-R1 Fadeouts Possible Possible Possible 10.7cm/SSN 145/99 142/96 138/92 COMMENT: Solar flare activity on UT day 29-May was at the R1 level due to an M1.1 flare at 29/0704UT. There are currently eight numbered sunspot regions visible on the solar disk. Newly rotated on Active Region (AR) 4455 (N14E46, beta) was responsible for the only R1 level flare event of the UT day. This region showed some spot decay. AR 4446 (S13W07, beta-gamma) showed spot development and 4452 (N09W44, beta-gamma) showed spot movement. These two regions are the most magnetically complex sunspot regions on the solar disk currently. All other sunspot regions are either stable or in decay. Solar flare activity is expected to be at R0-R1 levels over 30-May to 01-Jun. S0 solar radiation storm conditions were observed on UT day 29-May. S0 solar radiation storm conditions are expected over 30-May to 01-Jun. No Earth-directed coronal mass ejections (CMEs) have been observed. A west directed CME is visible from 29/0012UT in SOHO and STEREO-A imagery. This CME is considered a far side event and not geoeffective. The solar wind speed declined slightly on UT day 29-May, mostly ranging between 370 to 460 km/s and is currently near 420 km/s. The peak total interplanetary magnetic field strength (IMF, Bt) was 9 nT and the north-south IMF component (Bz) range was -8 to +5 nT. The solar wind speed is expected to remain at current levels over 30-May to 01-Jun, with a chance of an increase on 01-Jun due to a small equatorial coronal hole rotating towards a geoeffective position.

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