Weekly forecast

Solar activity forecast for the period January 16 - January 22, 2026

Activity level: low to moderate
X-ray background flux (1.0-8.0 A): in the range B7.5-C3.0
Radio flux (10.7 cm): a fluctuation in the range 105-178
Events: class C (2-12/day), class M (0-4/period), class X (0-1/period), proton (0-1/period)
Relative sunspot number (Ri): in the range 58-147

Vlastislav Feik
RWC Prague, Astronomical Institute, Solar Dept., Ondrejov, Czech Republic 

Geomagnetic activity forecast for the period January 16 - January 22, 2026

Quiet: Jan 16, 21 - 22
Unsettled: Jan 18 - 21
Active: Jan 17 - 19
Minor storm:   Jan 17 - 19
Major storm:  0
Severe storm: 0

Current geomagnetic activity trend shows partial activity decrease till Friday, January 16.
Because of large coronal hole 15/+4 approaching to the centre of solar disk, we expect geomagneteic activity increase the coming Saturday (January 17) to active level, generally. This activity level has been expected through the whole weekend, than, starting the new week, we expect a partial decrease to at most unsettled level.
The last two days, we expect quiet to unsettled conditions generally.

Tomas Bayer
RWC Prague
Institute of Geophysics of the ASCR, Prague
Department of Geomagnetism
Budkov observatory (BDV)

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere January 16 - January 22, 2026

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere, January 15, 2026

Within the 27-day fluctuation, as expected, the solar radio noise power flux curve on the wavelength of 10.7 cm passed through a minimum of 111 s.f.u. on January 11. Whereupon began to rise slowly. The rise will continue, mainly due to new activity around the southeastern limb of the solar disk, where the currently largest active region, AR4341, has emerged. Even before its emergence, it made itself known with M-class solar flares accompanied by CMEs.

Other significant formations on the Sun include three coronal holes. The second largest is now locted on the northwest part of the solar disk. The solar wind blowing from its edges is likely to cause a shorter increase in geomagnetic activity on January 17. Significantly stronger disturbances can be expected about a week later, when the large coronal hole will move from the southeast of the solar disk to the central meridian. This will happen simultaneously with AR4341, causing a significant increase in solar flux - and also geomagnetic activity.

F. K. Janda, A.R.S. OK1HH
http://ok1hh.nagano.cz/
Emails: ok1hh(at)crk.cz, ok1hh(at)rsys.cz
Pmail: OK1HH(at)OK0NAG.#BOH.CZE.EU

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