Summary and Forecast

Solar Summary

(last updated 26 Dec 2025 23:30 UT)

Activity 26 Dec: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 26 Dec: 166/120

Solar Forecast

(last updated 26 Dec 2025 23:30 UT)

27 Dec 28 Dec 29 Dec Activity R0-R1 R0-R1 R0-R1 Fadeouts Possible Possible Possible 10.7cm/SSN 170/124 175/129 170/124 COMMENT: Solar activity on UT day 26-Dec was R0. Solar region AR4317 (N11W03,beta) showed some umbral redistribution in its leader spot and decay in its trailer spots. Solar region AR4321 (S11W35, beta) is decaying with a decrease in umbral area and an increase in penumbral area and exhibits a north-south magnetic polarity orientation rather than the more typical east-west orientation. These two medium sized regions are the larger of the on disk regions. A new medium sized region is rotating onto the solar disk over the northeast limb at solar latitude N26. Region AR4323 (S10E80, alpha) is a small solar region in the southeast quadrant. Just to the southwest of this region are possibly the returned remnants of decayed AR4294 in an area of faculae and possibly very small spots/pores. There is still some east limb emission at S15 which may possibly be the return of AR4296, though the plasma arch activity doesn't appear to be that significant. Solar regions AR4317 and AR4323 produced isolated C class flare activity, with the largest a C6.9 at 26/0914UT from AR4323. There are currently eight numbered sunspot regions and one unnumbered region on the solar disk. All other sunspot regions are small and either stable or in decay. Solar activity is expected to be R0-R1 over 27-29 Dec. No Earth directed CMEs were observed on UT day 26-Dec. A faint south southeast directed CME was observed from 26/1436UT which could not be correlated to on disk activity. S0 solar radiation storm conditions were observed on UT day 26-Dec. S0 solar radiation storm conditions are expected over 27-29 Dec. The solar wind speed on UT day 26-Dec was moderate to strong and slightly declined as the influence of a coronal hole slowly abates. The solar wind speed ranged from 508 to 570 km/s and is currently at 520 km/s. The peak total interplanetary field strength (IMF, Bt) was 6 nT and the north-south IMF component range was +4 to -4 nT. The solar wind is expected to continue to slowly decline. Whilst the transequatorial section of the coronal hole that is currently influencing the solar wind is now well west on the solar disk, another shorter south polar extension section of this hole is now just past the solar central meridian. This may cause the solar wind to decline more slowly over coming days. An isolated coronal hole is visible in the northeast solar quadrant with centre location at N20E30.

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