Predikce sluneční a geomagnetické aktivity

Solar activity forecast for the period

November 24 - November 30, 2023

Activity level:	low to moderate
X-ray background flux (1.0-8.0 A):	in the range C1.0 - C1.8
Radio flux (10.7 cm):	a fluctuation in the range 150-230
Events:	class C (2-9/day), class M (0-7/period), class X (1/period), proton (0/period)
Relative sunspot number (Ri):	in the range 80 - 220

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

Geomagnetic activity forecast for the period

November 24 - November 30, 2023

Quiet:	Nov 24, 29 - 30
Unsettled:	Nov 23, 26 - 28
Active:	Nov 23, 27
Minor storm:	Nov 23, unlikely Nov 27
Major storm:	0
Severe storm:	0
Geomagnetic activity summary:	Today, we have recorded the geomagnetic activity at active level. Tomorrow, Thursday 23, we expect unstettled to active level of geomagnetic activity. Next day, since Friday, November 24, we expect geomagnetic activity decrease to quiet to unsettled level. Quiet to unsettled conditions are also expected at the end of currently forecasted period, November 29 - 30. This can be interrupted about Monday, November 27 when we can expect another active event because of influence of coronal hole 75/+4 located close the active region.

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

Geomagnetic activity forecast for the period

November 24 - November 30, 2023

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 November 24 - November 30, 2023
Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere – November 23, 2023

After passing through a twenty-seven day low in mid-November, solar activity began to increase. Slowly at first, then steeply in recent days. What was common to the whole period was that the predictions of further developments were not fulfilled. Shortwave propagation conditions were, with a few exceptions, worse than expected.

In the second half of last week, the Earth's magnetic field was calm despite the eruption of a magnetic filament on the Sun on November 16, which threw a CME almost directly towards the Earth. We expected the CME to arrive on November 19. On the contrary, quiet days followed on November 19-20. Then, despite seven new sunspot groups and calm in the Earth's magnetosphere, propagation conditions did not improve until November 20.

Improvement occurred on 21 November, when the onset of the geomagnetic disturbance was accompanied by two positive phases of development with increases in MUF and an overall improvement in CONDX (at intervals of 10-13 UT and 16-19 UT).

The following evolution could be expected - there was a deterioration of propagation conditions in the negative phase of the disturbance development on 22 November. However, the deterioration was short-lived, after which, thanks to the increasing solar activity, an improvement occurred already on 23 November.

Although solar activity continues to increase, there is a coronal hole near the five active regions in the northeast quadrant of the solar disk. This configuration will cause further increases in solar wind speed and therefore more frequent alternation of better and worse days.

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

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

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