Weekly forecast

Solar activity forecast for the period August 28 - September 03, 2026

Activity level: low to moderate 
X-ray background flux (1.0-8.0 A): in the range B3.0-B8.5
Radio flux (10.7 cm): a fluctuation in the range: 110-140
Events: class C (2-8/day), class M (1-3/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 75-130

Karolina Knesplova
RWC Prague, Astronomical Institute, Solar Dept., Ondrejov, Czech Republic 

Geomagnetic activity forecast for the period August 28 - September 03, 2026

Quiet:   Sep 1 - 2
Unsettled: Aug 30 - 31, Sep 3
Active:  Aug 28 - 29, Sep 3
Minor storm: Aug 28 - 29, Sep 3
Major storm:  possible Aug 28
Severe storm: 0
We expect a significant geomagnetic activity enhancement within the nearest coming hours.
Friday, August 28, and Saturday, August 29, we expect at most active conditions with probable magnetic storm.
Since August 31, we expect quiet to unsettled conditions return.
At the and of currently forecasted period, an another active event is possible. 

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 August 28 - September 03, 2026

More or less in line with expectations, total solar activity has been slightly elevated during the last third of August, including flare activity—we have been observing moderate-sized flares since August 24, peaking on August 25. Most sunspots and all larger groups are now located in the western half of the solar disk, which increases the likelihood of rising geomagnetic activity, which had been low for a relatively long period beginning on August 21. This resulted in above-average shortwave propagation conditions, including propagation in the Earth’s polar regions.

Solar activity is expected to remain elevated for the remainder of August and will drop significantly in early September. Geomagnetic activity, however, will increase, whilst is likely to remain higher for the rest of August. Consequently, shortwave propagation conditions will no longer be as consistent as in recent days; instead, there will be a decrease in usable frequencies and an increase in attenuation. The beginning of September will be calmer, albeit with slightly lower critical frequencies in the F2 layer of the ionosphere.

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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