Summary and Forecast

Solar Summary

(last updated 20 Jan 2026 23:30 UT)

Activity 20 Jan: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 20 Jan: 178/131

Solar Forecast

(last updated 20 Jan 2026 23:30 UT)

21 Jan 22 Jan 23 Jan Activity R1-R2 R1-R2 R1-R2 Fadeouts Possible Possible Possible 10.7cm/SSN 180/133 180/133 175/129 COMMENT: Solar flare activity on UT day 20-Jan was at the R0 level, with several low level C-class flares observed. There are currently ten numbered sunspot regions visible on the solar disk. AR4342 (N18W00, beta-gamma) is the most magnetically complex region on the disk and has exhibited spot development over the UT day. AR4345 (S16E03, beta) has shown spot growth over the 24-hour period. The other notable region, AR4341 (S11W04, beta), has shown mild decay in its leader spots. All other sunspot regions are either stable or in decay. Solar flare activity is expected to be at R1-R2 levels over 21-23 Jan. S2 solar proton conditions were observed on UT day 20-Jan. S1 solar proton conditions are expected on 21-Jan, declining to S0, with a chance of S1 over 21-22 Jan. No Earth-directed coronal mass ejections (CMEs) have been observed. The solar wind speed on UT day 20-Jan decreased, ranging from 785 to 1050 km/s and is currently near 825 km/s. The peak total interplanetary magnetic field strength (IMF, Bt) was 62 nT and the north-south IMF component (Bz) range was -26 to +60 nT. A sustained period of southward IMF conditions began at 20/0530UT and is ongoing. The solar wind speed is expected to decline over 21-23 Jan due to waning CME effects.

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