Weekly forecast

Solar activity forecast for the period April 03 - April 09, 2026

Activity level: low
X-ray background flux (1.0-8.0 A): in the range B7.5-C3.2
Radio flux (10.7 cm): a fluctuation in the range 132-165
Events: class C (0-9/day), class M (0-4/period), class X (0-1/period), proton (0/period)
Relative sunspot number (Ri): in the range 60-180

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

Geomagnetic activity forecast for the period April 03 - April 09, 2026

Tomáš Bayer 
	
14:27 (před 7 hodinami)
	
	
komu: Sunwatch, RWC, mně

Quiet:  Apr 6 - 8
Unsettled: Apr 4 - 6
Active: Apr 2 - 3, 9
Minor storm:   Apr 3, 9
Major storm:  Apr 3
Severe storm: 0

Currently, we have observed a geomagnetic activity increase. During the coming night, we expect the first geomagnetic activity peak.
Next days, we expect a partial activity decrease to at most unsettled level.
Since Monday, April 6, we expect geomagnetic activity decrease to quiet to unsettled level.
The last day, April 9, an active episode with possible storming event can 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 02 - April 09, 2026

Updated Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere, April 2, 2026

Developments from yesterday evening have finally allowed me to update both the overview and the forecast.

The increase in overall solar activity during the third ten-day period of March—albeit with a slight delay—led to a gradual rise in MUF values, extending into the first days of April. An increase in solar flare activity did not occur until April 30, beginning with a flare at 0319 UT with an X-ray intensity of X1.4, which lasted a long time and was accompanied by a CME. Since a large coronal hole No. 36 was located nearby, a significant increase in geomagnetic activity was expected. This did not occur until April 2, but already during several preceding active intervals, we could observe the effects of electromagnetic wave scattering on ionospheric inhomogeneities, clearly visible even on ionograms.

Active region NOAA 4405, located 27 degrees south of the solar equator, has been clearly visible for a week as the largest on the solar disk and appears to be stable. On April 3, it passes the central meridian, and its proximity to coronal hole No. 36 is a potential source of intensified solar wind. It also indicates higher geomagnetic activity (at G2 level since April 2). This proximity will likely be the cause of increased geomagnetic activity during the first ten days of April. Consequently, this will lead to irregular shortwave propagation conditions and more frequent drops in the MUF.

The next increase in solar activity will likely occur in the last third of April. Daily MUF values will rise again, and at the same time, a sporadic E layer will begin to appear occasionally in mid-latitudes. Although it will not yet have a significant impact on shortwave propagation, it will occasionally cause interesting DX openings on the shortest shortwave bands.

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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