Summary and Forecast

Solar Summary

(last updated 04 Jan 2026 23:30 UT)

Activity 04 Jan: R0 Flares: none. Observed 10.7 cm flux/Equivalent Sunspot Number for 04 Jan: 157/111

Solar Forecast

(last updated 04 Jan 2026 23:30 UT)

05 Jan 06 Jan 07 Jan Activity R1, chance R2 R1, chance R2 R1 Fadeouts Possible Possible Possible 10.7cm/SSN 155/109 150/105 145/99 COMMENT: Solar activity on UT day 04-Jan was at the R0 level, with no significant flare activity observed over the past 24 hours. There are currently seven active regions on the Sun, with Active Region (AR) 4325 (S09W47, beta) being the largest. This region has shown minor decay over the last UT day. Active Region 4334 (S15E50, alpha) has exhibited some growth over the same period. Newly numbered AR 4336 has recently rotated onto the front side of the disk at S08W77 and currently displays an alpha magnetic classification. All other regions are either stable or in decay. Solar activity is forecast to reach the R1 level, with a chance of R2 over 05-06 Jan due to the past flare activity of AR 4325 and 4324. This is expected to decline to R1 on 07-Jan as these regions rotate towards the western limb. S0 solar radiation storm conditions were observed over the past 24 hours, with the proton flux at background levels. S0 conditions are forecast to persist over the period 05-07 Jan. No new geoeffective Coronal Mass Ejections (CMEs) were observed over the past UT day. The solar wind speed was slightly elevated on 04-Jan, ranging between 420 - 460 km/s throughout most of the day. This has become elevated over the last few hours, with current speeds between 470-500 km/s, likely due to a glancing impact from a CME first observed on 01-Jan. The interplanetary magnetic field strength (IMF, Bt) was low throughout most of UT day 04-Jan, but has recently risen to a peak of 10 nT due to the CME arrival. The north-south component (Bz) ranged between -8 and +5 nT during the past 24 hours, with a period of extended southward Bz between 04/2045 - 2220 UT. The solar wind is expected to remain elevated during the early part of 05-Jan due to the ongoing impact of this CME. The solar wind speed will then trend towards background levels over 06-07 Jan, as the effects of this CME diminish.

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