Weekly forecast

Solar activity forecast for the period June 13 - June 19, 2025

Activity level: low to moderate
X-ray background flux (1.0-8.0 A): in the range B4.5-C4.0
Radio flux (10.7 cm): a fluctuation in the range 90-175
Events: class C (3-12/day), class M (0-3/period), class X (0-1/period), proton (0-1/period)
Relative sunspot number (Ri): in the range 35-160	

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

Geomagnetic activity forecast for the period June 13 - June 19, 2025

Quiet: Jun 17 - 19
Unsettled: Jun 13, 15 - 18
Active: Jun 13 - 14
Minor storm:  13 - 14
Major storm:  0
Severe storm: 0

We expect geomagnetic intensity enhancement during the coming weekend, it can occur just in Friday, June 13.
About Saturday, June 14, an active event with a storming event is possible.
Since Sunday, June 15, we expect geomagnetic activity decrease to unsettled level. !
Last days, since Tuesday, June 17, we expect geomagnetic activity decrease to quiet to unsettled level. 

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 June 13 - June 19, 2025

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere – June 12, 2025

The observed number of sunspot groups ranged between five and six until June 10. A change occurred on June 11, when four more groups appeared in the northeast of the solar disk, followed immediately by a fifth. Which quickly manifested itself in a slight increase in solar flux. However, since the afternoon of June 11, the activity of the Earth's magnetic field increased, so therefore a noticeable decrease in MUF followed on June 12.

Fortunately, propagation conditions in the shortwave DX bands (usually understood to mean frequencies above 14 MHz) were diversified by the more frequent occurrence of the sporadic E layer. Although irregular and with only short rises in MOF Es towards 30 MHz, it revived the DX bands despite the decline in MUF F2 (by up to several MHz during the day).

Solar activity will temporarily increase slightly in the second half of June, but this will have little effect on shortwave propagation conditions. There is greater hope for a slight improvement and more interesting developments from mid-June onwards. However, shortwave propagation conditions in the last days of the month will again be less regular and slightly disrupted.

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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