ARRL Headquarters was closed on November 29. So, this regular Friday
bulletin was moved to the following Monday (12/2).

Solar activity increased during the current reporting week, November
21-27. Average daily sunspot number rose to 155.7, and average daily
solar flux was 282.2.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere - November 28, 2024, by F. K. Janda, OK1HH:

"After the unexpected solar proton flare of 21 November, which took
place beyond the Sun's western limb, a rain of higher-energy protons
hit the Earth's atmosphere. This solar radiation storm had a greater
impact at higher latitudes in the southern hemisphere, where it
caused a significant increase in attenuation.

"Two days later, two new large sunspot groups appeared near the
southeastern limb of the Sun. These produced moderate eruptions
daily, which is more or less normal for the 11-year maximum. These
are AR3905 and AR3906, which have grown rapidly to a size where they
can be observed with the naked eye. There is a relatively small
coronal hole near them that could be influencing the solar wind
enhancement.

"Following the eruption of a plasma filament near AR3901, a G2 class
geomagnetic storm is possible on November 28-29, when a CME is
expected to impact. However, around 1900 UT on November 28, when
this information is written as usual, nothing is still happening. We
will see what happens next. It is quite possible that the plasma
cloud will only hit the Earth a little and it is also not out of the
question that it will miss the Earth completely. So, any prediction
at this point has a low probability of coming true."

New video from Dr. Tamitha Skov, WX6SWW:

https://youtu.be/1P4sCwn8TZI

Send your tips, reports, observations, questions and comments to
k7ra@arrl.net. When reporting observations, don't forget to tell us
which mode you were operating.

For more information concerning shortwave radio propagation, see
http://www.arrl.org/propagation and the ARRL Technical Information
Service web page at, http://arrl.org/propagation-of-rf-signals. For
an explanation of numbers used in this bulletin, see
http://arrl.org/the-sun-the-earth-the-ionosphere .

An archive of past propagation bulletins is at
http://arrl.org/w1aw-bulletins-archive-propagation . More good
information and tutorials on propagation are at http://k9la.us/ .

Also, check this:

https://bit.ly/3Rc8Njt

"Understanding Solar Indices" from September 2002 QST.

Instructions for starting or ending email subscriptions to ARRL
bulletins are at http://arrl.org/bulletins .

Sunspot numbers for November 21 through 27, 2024 were 148, 170, 156,
164, 140, 163, and 141, with a mean of 155.7. 10.7 cm flux was
166.2, 179.1, 199.9, 202.7, 220.4, 222.3, and 225, with a mean of
202.2. Estimated planetary A indices were 8, 12, 8, 7, 11, 7, and 5,
with a mean of 8.3. Middle latitude A Index was 5, 10, 7, 7, 9, 6,
and 3, with a mean of 6.7.