Weekly forecast

Solar activity forecast for the period April 10 - April 16, 2026

Activity level: low
X-ray background flux (1.0-8.0 A): in the range B1.0-B9.5
Radio flux (10.7 cm): a fluctuation in the range: 87-123
Events: class C (1-6/day), class M (0-1/period), class X (0-1/period), proton (0-1/period)
Relative sunspot number (Ri): in the range 44-125

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

Geomagnetic activity forecast for the period April 10 - April 16, 2026

Quiet:  Apr 13 - 16
Unsettled: Apr 11 - 13
Active: Apr 10 - 11
Minor storm:   Apr 10 - 11
Major storm:  0
Severe storm: 0

Next two days, we expect a geomagnetic activity increse to an active level with possible minor storm event.
Then, since Sunday, April 12, we expect a partial decrease to at most unsettled level.
The last days, we expect at most quiet conditions return. 

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 April 10 - April 16, 2026

Perhaps the biggest surprise in recent days was that, following the geomagnetic disturbance of April 2–3 (which had been expected, albeit a day earlier and with lower intensity), there were no further major surprises. Solar activity declined as predicted, whereas because it declined over a relatively long period, there was a greater-than-expected drop in critical frequencies in the F2 ionospheric region at mid-latitudes.

For forecasting developments in the second third of April, the 27-day cycle could serve as a relatively reliable guide this time. First of all, one might expect a one- to two-day increase in geomagnetic activity (which is also indicated by the presence of solar coronal holes near the central meridian), followed by relative calm. This is despite the short time that has elapsed since the eleven-year peak of solar 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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