Weekly forecast

Solar activity forecast for the period October 09 - October 15, 2026

Activity level: low to moderate
X-ray background flux (1.0-8.0 A): in the range B7.0-C2.0
Radio flux (10.7 cm): a fluctuation in the range: 95-149
Events: class C (0-6/day), class M (0-3/period), class X (0/period), proton (0/period)
Relative sunspot number (Ri): in the range 34-97

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

Geomagnetic activity forecast for the period October 09 - October 15, 2026

Quiet:   Oct 11 - 13
Unsettled: Oct 10 - 11, 14 - 15
Active:  Oct 9 - 10, 14 - 15
Minor storm: Oct 9, 14 - 15
Major storm:  0
Severe storm: 0

Last week, we had recorded a major storm event (K-index 6, October 4).
After a partial activity decrease (currently, the geomagnetic field is at most quiet), we expect active conditions return tomorrow, i.e. Friday, October 9, with possible minor storm event.
Comparable activity level can occur at the end of currently forecasted period, since October 14.
Between these events, we expect at most a quiet to unsettled intermezzo.

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 October 09 - October 15, 2026

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere, October 8, 2026

The decline in solar activity, which had already been on the horizon in August, occurred during the third decade of September and in the first days of October. Then, as if by magic, on October 5, active region NOAA AR 4549 appeared in the center of the solar disk; it grew rapidly and had the right magnetic configuration to trigger energetic flares. It is therefore no surprise that shortly after midnight UT on October 6, it became the source of two moderately strong flares, accompanied by coronal mass ejections (CMEs). Based on the speed of the particle clouds heading toward Earth, a geomagnetic disturbance can be expected on October 9. If it begins during daylight hours, we can expect a positive phase to develop. Over the following weekend, we should expect a negative phase.

The decline and subsequent increase in solar activity over the past few weeks can be seen as a precursor to heightened solar activity over the next 2–3 months. After that, solar activity will continue to decline toward the minimum of the 11-year cycle.

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

Receive Weekly Forecasts Bulletin

To receive Weekly Forecasts Bulletin via email, sign up for: sunwatch "at-sign" asu.cas.cz