Predikce sluneční a geomagnetické aktivity

Solar activity forecast for the period

July 26 - August 01, 2024

Activity level:	mostly moderate
X-ray background flux (1.0-8.0 A):	in the range C1.0 - C7.0
Radio flux (10.7 cm):	a fluctuation in the range 160-260
Events:	class C (3-15/day), class M (2-16/period), class X (0-1/period), proton (0-1/period)
Relative sunspot number (Ri):	in the range 100-300

Michael Vavra
RWC Prague, Astronomical Institute, Solar Dept., Ondrejov, Czech Republic
e-mail: sunwatch(at)asu.cas.cz

Geomagnetic activity forecast for the period

July 26 - August 01, 2024

Quiet:	Jul 29 - 31
Unsettled:	Jul 27 - 28, Aug 1
Active:	Jul 27 - 28
Minor storm:	Jul 26 - 27
Major storm:	unlikely Jul 27
Severe storm:	0
Geomagnetic activity summary:	Because of the last CME set, we expect geomagnetic activity within coming two days. We expect a minor, or, unlikely major storm during this time interval. Since July 28, we expect geomagnetic activity decrease to unsettled level and, since July 29, quiet to unsettled conditions generally. The last day of currently forecasted period, another geomagnetic activity enhancement is possible. Nevertheless, it should vary at the range of unsettled to active level.

Tomas Bayer, RWC Prague
Institute of Geophysics of the ASCR, Prague
Department of Geomagnetism
Budkov observatory (BDV)

Geomagnetic activity forecast for the period

July 26 - August 01, 2024

Geomagnetic field will be:

Quiet on:
Quiet to unsettled on:
Quiet to active on:
Unsettled to active on:
Active to disturbed:
Solar wind will intensify on:

Remarks:

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere July 26 - August 01, 2024

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere – July 25, 2024

So here we are on Thursday, July 25th. Initially it appeared that there would be a continued period of high solar activity, including flare activity. A logical continuing chain of predictions of increased geomagnetic activity, especially after major flares. Then finally at 1351 UTC a message came from NOAA containing the words: "WARNING: Geomagnetic Sudden Impulse expected. IP Shock Passage Observed: 2024 Jul 25 1315 UTC." The development continued and we could read the message from Boulder, Co.: "SUMMARY: Geomagnetic Sudden Impulse Observed: 2024 Jul 25 1422 UTC. Deviation: 8 nT. Station: BOU." After all, after a series of solar flares, this was no longer a major surprise while the week-old forecast by Tomáš Bayer (RWC Prague, Department of Geomagnetism, Budkov Observatory (BDV)) was fulfilled.

But it was not a big surprise, the previous major disturbance occurred on 28 June, or 26 days ago. If the mentioned geomagnetic disturbance develops and lasts longer, it will adversely affect the shortwave propagation conditions in the following days, possibly until Sunday.
However, the recovery could be even faster due to the high solar activity.

F. K. Janda, A.R.S. OK1HH

e-mail: ok1hh(at)crk.cz; ok1hh(at)rsys.cz

Pmail: OK1HH(at)OK0NAG.#BOH.CZE.EU