Solar activity forecast for the period May 22 - May 28, 2026

Activity level: low to moderate
X-ray background flux (1.0-8.0 A): in the range B6.5-C2.1
Radio flux (10.7 cm): a fluctuation in the range: 110-145
Events: class C (1-8/day), class M (0-5/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 55-132

Martina Pavelkova
RWC Prague, Astronomical Institute, Solar Dept., Ondrejov, Czech Republic 

Geomagnetic activity forecast for the period May 22 - May 28, 2026

Quiet:  May 24 - 26
Unsettled: May 22 - 23, 27
Active: May 27 - 28
Minor storm:   about May 28
Major storm:  0
Severe storm: 0

Next days, we expect geomagnetic activity decrease generally. From current conditions, at most unsettled, we expect a partial decrease to quiet to unsettled level (quietest about Tuesday, May 26).
Then, at the end of currently forecasted period, active conditions with possible minor storm can occur again.

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 May 22 - May 28, 2026

The number of sunspot groups on the solar disk ranged from three to seven over the past week; their total area was not large, while their magnetic structure was relatively simple. Nevertheless, isolated C-class flares were recorded. In addition, there was even an M-class flare recorded  on Sunday, May 17 (in AR 4435 near the northwestern limb of the solar disk, peaking at 0339 UT). Thanks to the Solar Orbiter probe, however, we know that the situation will change. Because, in a location where there was no group of sunspots during the previous solar cycle, not only is there a group now, but it is also quite extensive. Its edge is already slowly beginning to appear on the southeastern limb of the solar disk. While a week later, we can expect the peak of activity within the current solar rotation.

The geomagnetic field will be mostly quiet to unsettled in the coming days, after which its activity will rise, initially slightly—and a disturbance can be expected toward the end of the month. This will result in a generally favorable development for the ionosphere for the remainder of May. This includes increases in geomagnetic activity, during which, depending on the timing, MUF values may temporarily rise.

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