\n<\/p>\n
Solar activity was at low levels this past week with only C class
flares. Region 4294 remains the largest region on the disk but is
appearing to be simplifying magnetically. Region 4296, on the other
hand, gained a delta region in its intermediary region, though with
no corresponding increase in flare activity as of yet. New flux
emerged along the eastern side of Region 4298, resulting in several
C flares throughout the reporting period. Region 4299 also developed
a delta region in its primary spot but no appreciable shear was
observed. Region 4301 developed, was numbered, but was otherwise
unremarkable. No Earth directed CMEs were observed in available
coronagraph imagery.
\u00a0
Isolated to occasional M class flares are expected through December
6, with a chance for X class flares, given past flare history, and
the potential of current active regions on the disk.
\u00a0
The environment will likely remain enhanced due to fast solar wind
conditions through December 6.<\/p>\n
M class flares (R1 to R2\/Minor to Moderate) are likely, with slight
chance for X flares (R3 Strong or greater), through 12 Dec due
primarily to the flare potential of Region 4294.<\/p>\n
Geomagnetic activity is likely to reach active levels on December 3
and 6, and G1 (Minor) storm levels on December 4 and 5, driven by
influences from a negative polarity CH HSS.<\/p>\n
Weekly Commentary on the Sun, the Magnetosphere, and the Earth’s
Ionosphere, December 4, 2025, by F. K. Janda, OK1HH:<\/p>\n
The significant increase in solar activity since the beginning of
December has finally confirmed the original assumption that the
current 25th eleven year solar cycle will have two peaks. The first
occurred last October, while we have been eagerly awaiting the
second this year (especially in the fall). The increase in activity
at the end of this summer started promisingly, but it was only the
first of several. It was only after the large solar flare on
November 11, 2025, which was the largest since October 3, 2024, that
it was possible to estimate that the second maximum was approaching.<\/p>\n
High solar activity period can be expected during the first half of
December, while it is a bit of a shame that it did not occur a week
or two earlier. This would have been particularly appreciated by
shortwave radio amateurs, as the telegraph part of the largest
competition, the CW WW DX Contest,\u00a0 traditionally takes place
during the last weekend of November.<\/p>\n
Although the current parameters of high speed solar wind do not
create exactly the structure of the Earth’s ionosphere that we would
like, at least the highest usable frequencies allow connections to
be established on all shortwave bands. During December, we are
likely to experience another increase in solar activity in the last
third of the month, preceded by several days of increased
geomagnetic activity.<\/p>\n
The latest video report from Dr. Tamitha Skov, WX1SWW, can be found
on Youtube.<\/p>\n
The Predicted Planetary A Index for December 6 to 12 is 12, 10, 8,
5, 5, 5, 8 with a mean of 7.5. Predicted Planetary K Index is 4, 3,
3, 2, 2, 2, and 3, with a mean of 2.7. 10.7 centimeter flux is 190,
190, 190, 190, 185, 180, and 180, with a mean of 186.4.
\u00a0
For more information concerning shortwave radio propagation, see
and the ARRL Technical Information
Service web page at, For
an explanation of numbers used in this bulletin, see
. Information and
tutorials on propagation can be found at, .<\/p>\n
Also, check this:<\/p>\n
https:\/\/bit.ly\/3Rc8Njt<\/p>\n