10/17/2025

Region AR4246 underwent significant evolution, growing in overall
size while gaining multiple new spots. Subsequently, AR4246 was the
main provider of activity which included an M1.2 flare on October
13. Several coronal mass ejections (CMEs) with potential
Earth-directed components are in the mix at this time.

Additional modeling efforts are underway to perhaps confirm those
suspicions. The largest flare was a long-duration M4.8/2n on October
15. Modeling efforts showed the ejecta to be on a northward
trajectory and not on an Earthward course.
ÿ
Other notable activity included a prominence eruption off the ENE
limb-first visible in LASCO C2 imagery on October 14. Given the
location of the event, initial analysis suggests this ejecta to be
well into foul-ball territory and not Earth-directed. Additional
modeling efforts are underway to perhaps confirm this suspicion.
ÿ
Slight decay was observed in the intermediate portion of Region
AR4248 as it grew in length. Region AR4247 was in decay as well. The
remaining regions were unremarkable in comparison. No new regions
were assigned numbers this period. Minor to moderate (R1-R2) radio
blackouts are likely for the next 3 days, with a slight chance for
an isolated R3 (strong) event, due to the current and potential
flare activity of Regions AR4246 and AR4248.
ÿ
Solar wind parameters continued to reflect the influence of a
negative polarity coronal hole high speed stream (CH HSS). Solar
wind speeds finally dipped below 600 km/s and phi was predominantly
in the negative solar sector.
ÿ
Solar wind parameters are expected to continue at enhanced levels,
although gradually waning, and continuing through October 17, due to
CME arrivals from the October 11 to 13 timeframe originating from
AR4246.ÿ Solar activity reached moderate levels due to M-class flare
activity.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere, October 16, 2025, by F. K. Janda, OK1HH:

"In line with forecasts, solar activity continued to gradually
increase, including several moderately strong flares. These were
mostly observed in the active region NOAA 4246, located in the
northwest of the solar disk, while approaching its limb.

"The second of the two larger active regions is NOAA 4248, also
located in the northwest, but closer to the central meridian and the
solar equator, while relatively close to the extensive coronal hole
No. 87. In the coming days, AR NOAA 4248 will move into the active
longitudes. Therefore, its eruptive activity will increase. Between
it and the aforementioned coronal hole, a source of intensified
solar wind will form, which will hit Earth during the coming week.

"Even earlier, on October 16, when this text is being written, we
expect a G2 geomagnetic disturbance, which will first cause a brief
improvement and then a deterioration in ionospheric propagation of
short waves, which have been rather average so far. The exception
was a shorter increase in MUF on October 15 between 1000 and 1200
UTC, probably caused by an intensification of the solar wind.

"Solar activity should remain at current levels for the rest of the
month. Fluctuations in propagation conditions, mostly around average
with occasional deterioration, will depend on the irregular
occurrence of geomagnetic disturbances."
ÿ
The latest video report from Dr. Tamitha Skov, WX6SWW, can be found
on YouTube at:ÿ https://www.youtube.com/watch?v=pAZtua4DZUs[1] .
ÿ
For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation[2] and the ARRL Technical Information
Service web page at, http://arrl.org/propagation-of-rf-signals[3]. For
an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere[4] . Information and
tutorials on propagation can be found at, http://k9la.us/[5] .

Also, check this:

https://bit.ly/3Rc8Njt[6]

"Understanding Solar Indices" from September 2002 QST.

The Predicted Planetary A Index for October 18 to 24 is 5, 5, 15,
10, 8, 5, and 5, with a mean of 7.6.ÿ Predicted Planetary K Index is
2, 2, 5, 3, 3, 2, and 2, with a mean of 2.7.ÿ 10.7-centimeter flux
is 150, 150, 150, 150, 145, 140, and 145, with a mean of 147.1.
ÿ


[1] https://www.youtube.com/watch?v=pAZtua4DZUs
[2] http://www.arrl.org/propagation
[3] http://arrl.org/propagation-of-rf-signals
[4] http://arrl.org/the-sun-the-earth-the-ionosphere
[5] http://k9la.us/
[6] https://bit.ly/3Rc8Njt

---
þ Synchronet þ Whiskey Lover's Amateur Radio BBS

10/31/2025

Solar activity has decreased to very low levels. Region 4266
exhibited signs of slight development as it gained asymmetric
penumbra surrounding its trailing spots. Meanwhile, Region 4267
underwent decay, losing several leading spots. Additional activity
included a coronal mass ejection (CME) off the NE limb on October
29.
ÿ
An associated Type II radio sweep was reported with the CME; however
SUVI 195 imagery revealed the CME to have originated on the far
side. Also, an approximate 12 degree filament eruption, centered
near N27W24 was observed becoming unstable beginning October 29.
Most of the material of this event appeared to have been reabsorbed
with perhaps a faint and narrow CME escaping. Modeling of this event
revealed a possible glancing blow to the north of Earth by late on
November 2, but confidence is low in both the analysis of this event
and the modeling outcome.
ÿ
Solar wind parameters continued to reflect positive polarity coronal
hole high speed stream (CH HSS) influences. Solar wind parameters
are expected to continue to reflect positive CH HSS influences
through November 1.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere, October 30, 2025, by F. K. Janda, OK1HH:

"It is very rare for the situation on the Sun and between it and
Earth to be as relatively simple and clear as it has been in recent
days. This is one of the reasons why it was possible to make a
fairly accurate prediction of further developments. Although there
were concerns that an intensified solar wind could hit Earth as
early as October 26, the original forecast ultimately proved
accurate and the disturbance began on October 28. The last weekend
in October was thus marked by relatively good conditions for radio
wave propagation on all shortwave bands.

"Regular helioseismological observations of the far side of the Sun
are closely monitoring the only two currently active regions on the
Sun. They will begin to emerge on the eastern edge of the solar disk
in the first half of next week, which will immediately be reflected
in an increase in solar flux. This may peak around October 10, but
it seems that it will happen sooner.

"The increase in solar activity during the usual favorable seasonal
changes alone will result in improved conditions for shortwave
propagation. With a little luck, the improvement could peak around
November 8, when the next increase in geomagnetic activity can be
expected."

Solar activity is expected to be at moderate levels until November
15 due to the return of Region 4246. Low levels are expected to
prevail from November 14 to 22 as multiple regions depart the
visible disk.

A greater than 2 MeV electron flux at geosynchronous orbit is
expected to be at high levels until November 15 due to responses
from recurrent CH HSS influences.ÿ Moderate levels are expected from
November 16 to 22.

Geomagnetic field activity is expected to be at quiet to unsettled
levels on November 1 to 6, 10 to 14, and November 16 to 22.ÿ Active
conditions are expected from November 7 to 9, and November 15.

The latest video report from Dr. Tamitha Skov, WX6SWW, can be found
on YouTube at, https://www.youtube.com/watch?v=y8uEPcivbQ8[1] .

Spaceweather.com[2] for October 31 reports on "Halloween Fireballs" and
the rapid brightening of Comet 3I/ATLAS.

The Predicted Planetary A Index for November 1 to 7 is 8, 5, 5, 5,
5, 5, 8, and 12, with a mean of 6.9.ÿ Predicted Planetary K Index is
3, 2, 2, 2, 2, 3, and 4, with a mean of 2.6.ÿ 10.7-centimeter flux
is 130, 130, 135, 140, 140, 140, and 140, with a mean of 136.4.

For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation[3] and the ARRL Technical Information
Service web page at, http://arrl.org/propagation-of-rf-signals[4]. For
an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere[5] . Information and
tutorials on propagation can be found at, http://k9la.us/[6] .

Also, check this:

https://bit.ly/3Rc8Njt[7]

"Understanding Solar Indices" from September 2002 QST.

ÿ


[1] https://www.youtube.com/watch?v=y8uEPcivbQ8
[2] http://Spaceweather.com
[3] http://www.arrl.org/propagation
[4] http://arrl.org/propagation-of-rf-signals
[5] http://arrl.org/the-sun-the-earth-the-ionosphere
[6] http://k9la.us/
[7] https://bit.ly/3Rc8Njt
---
þ Synchronet þ Whiskey Lover's Amateur Radio BBS

10/24/2025

Solar activity reached moderate levels this past week, but has now
returned to, and remains at, lower levels. Region 4248 produced an
M1.1 flare on October 20, which was the largest event of the period.
Region 4261 was numbered this period as it rotated into better
viewing conditions.

Region 4262 was numbered this period as well, splitting it from
Region 4257. Additionally, new spots were noted near N08W00 and
N09E67 but went unnumbered due to a lack of flaring and time of
emergence. No Earth-directed CMEs were observed in available
coronagraph imagery. Solar activity is expected to remain low, with
a chance for isolated M-class flares (R1-R2/minor-moderate).
ÿ
Additional notable activity included a type II radio sweep with an
estimated speed of 2,474 km/s and a type IV radio sweep that began
on October 21. Significant field line movement, appearing to
originate from beyond the northwestern limb, was observed in GOES
SUVI imagery beginning on October 21.ÿ The subsequent coronal mass
ejection (CME) was then first seen on LASCO C2 coronagraph imagery
on October 21. This event has been analyzed as a far-sided
asymmetric halo.
ÿ
Solar wind parameters were mildly enhanced this period due to
negative polarity coronal hole high speed stream (CH HSS)
influences. Solar wind speeds exhibited a decreasing trend from
approximately 600 km/s to under 500 km/s by the period's end. Phi
was predominantly positive while undertaking brief excursions into
the positive solar sector. Mildly enhanced solar wind conditions and
waning negative polarity CH HSS influences were expected to
continue.

Solar activity is expected to be at moderate levels from October 31
to November 15 due to the return of Region 4246. Low levels are
expected to prevail to October 30, and then on November 14 and 15.
Geomagnetic field activity is expected to reach G1-G2
(Minor-Moderate) storm levels on October 28 to 30.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere, October 23, 2025, by F. K. Janda, OK1HH:

"Although it may not seem so at first glance, solar activity is
still at the peak of its 25th cycle. Although the number of sunspot
groups fell to six in mid-October, a week later it had risen to ten.
Few eruptions were observed on the solar disk, or the side of the
Sun facing Earth, including only a few that could be classified as
moderately strong based on the intensity of X-ray emissions.

"However, something is brewing on the far side of the Sun. This is
evidenced by the occurrence of three CMEs, the first on October 21
and the other two on October 22. The increased concentration of
protons with an energy of 10 MeV (and a lower concentration of 100
MeV) in the solar wind confirms that this is significant activity.
To analyze the development of the relevant activity, we will have to
wait until it appears on the eastern limb of the solar disk.

"The geomagnetic field has calmed down in recent days. The next
disturbance is expected around October 28. At first glance, this is
very good news for shortwave propagation conditions during the
weekend of October 25-26, but if geomagnetic activity increases
during these days, it will come as no surprise.

"In fact, with the right timing of the disturbance, it could be
followed by an increase in MUF and an overall improvement. Although
a significant deterioration in propagation conditions is expected
with a relatively high probability only after the aforementioned
disturbance (i.e., around October 29), it may occur earlier."

The Predicted Planetary A Index for October 25 to 31 is 10, 5, 5,
25, 35, 25, and 15, with a mean of 17.1.ÿ Predicted Planetary K
Index is 3, 2, 2, 5, 6, 5, and 4, with a mean of 3.9.ÿ 10.7-centimeter flux is 150, 150, 150, 145, 145, 145, and 140, with a mean of 146.4.

For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation[1] and the ARRL Technical Information
Service web page at, http://arrl.org/propagation-of-rf-signals[2]. For
an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere[3] . Information and
tutorials on propagation can be found at, http://k9la.us/[4] .

Also, check this:

https://bit.ly/3Rc8Njt[5]

"Understanding Solar Indices" from September 2002 QST.

ÿ


[1] http://www.arrl.org/propagation
[2] http://arrl.org/propagation-of-rf-signals
[3] http://arrl.org/the-sun-the-earth-the-ionosphere
[4] http://k9la.us/
[5] https://bit.ly/3Rc8Njt
---
þ Synchronet þ Whiskey Lover's Amateur Radio BBS

11/14/2025

There were two nights of visible aurora throughout the continental
US and dead HF bands due to a severe geomagnetic storm caused by
what Space.com[1] calls "a colossal X5.1 class solar flare" and
associated coronal mass ejection (CME) on Tuesday, November 11.

Spaceweather.com[2] for November 14 reports that a NASA model of the
latest CME suggests that it could deliver a glancing blow to our
planet's magnetic field late on November 16.
ÿ
Meanwhile, Region 4274 was responsible for multiple low- to
mid-level C-class flares. The largest was a C4.5/Sf on November 12.
Slight decay was observed in Region 4274. Motion along the inversion
lines was minimal within the group. The rest of the spot groups were
either stable or in decay. No Earth-directed CMEs were observed.
ÿ
Solar activity is now forecast to be high, with R1-R2
(Minor-Moderate) expected and X-class (R3-strong) activity likely on
November 15, mostly due to the flare potential of Region 4274.
ÿ
Solar wind parameters continued to reflect persistent negative
polarity coronal hole high speed stream influences (CH HSS).ÿ Solar
wind speeds were between 450 km/s and 600 km/s. Phi was variable
through the first half of the period before turning mostly negative
for the second half. The solar wind environment had likely become
mildly enhanced with CME influences on November 10 as the November 7
CME passed in close proximity to Earth. Stronger solar wind
disturbances were likely over November 11-12 due to the anticipated
arrival of the November 9 asymmetric halo CME.

R1-R2 (Minor-Moderate) radio blackouts are likely, with a chance for
an isolated R3 (Strong) event, through 16 November primarily due to
AR4274s past flare history coupled with its current potential.

The geomagnetic field is expected to be quiet to unsettled levels on
November 15.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere, November 13, 2025, by F. K. Janda, OK1HH:

"In October, during the last solar rotation, two active regions on
the Sun: AR4246 and AR4248 were very interesting. Although they were
not the largest, their magnetic configuration indicated a possible
further increase in eruptive activity. This was confirmed during the
following parade on the far side of the Sun, when we could observe
several more powerful CMEs, especially on the eastern limb of the
solar disk.

"After their emergence on the disk, the culprit was reliably
identified as the AR4246 region, now AR4274, which continued to grow
to three times its October size. Above all, on November 9, 10, and
11, it produced a series of three large solar flares, each of which
was significantly more powerful than the previous one, including an
increase in the energy of the ejected protons by one order of
magnitude.

"The particle cloud from the second flare was faster than the one
from the first. It caught up with and cannibalized it, reaching
Earth after midnight UT on November 12 and causing powerful
geomagnetic disturbances accompanied by auroras visible at
mid-latitudes. It had the greatest impact on the ionosphere on
November 12, when MUF values dropped and attenuation increased.
After that, however, shortwave propagation conditions behaved very
unusually and interestingly.

"A sporadic-E layer appeared, ionospheric waveguides were formed,
allowing communication with very low transmitter power,
trans-equatorial routes opened up excellently, and, conversely,
routes leading through the auroral oval closed. The propagation of
radio waves through the polar region was further complicated by
attenuation in the polar cap (PCA).

"Until the AR4274 region fades away in a few days, we can expect
more similar surprises, although probably not as powerful. Solar
activity will begin to decline in the coming days, with geomagnetic
activity likely to decline a little later."

The latest report from Dr. Tamitha Skov, WX6SWW, can be found on
YouTube at, https://www.youtube.com/watch?v=RMSpOSTrcS4[3] .

The Predicted Planetary A Index for November 15 to 21 is 5, 10, 10,
5, 5, 12, and 10, with a mean of 8.1.ÿ Predicted Planetary K index
is 2, 3, 3, 2, 2, 4, and 3, with a mean of 2.7.ÿ Predicted
10.7-centimeter flux is 170, 165, 170, 165, 160, 155, and 155, with
a mean of 162.9.

For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation[4] and the ARRL Technical Information
Service web page at, http://arrl.org/propagation-of-rf-signals[5]. For
an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere[6] . Information and
tutorials on propagation can be found at, http://k9la.us/[7] .

Also, check this:

https://bit.ly/3Rc8Njt[8]

"Understanding Solar Indices" from September 2002 QST.

ÿ


[1] http://Space.com
[2] http://Spaceweather.com
[3] https://www.youtube.com/watch?v=RMSpOSTrcS4
[4] http://www.arrl.org/propagation
[5] http://arrl.org/propagation-of-rf-signals
[6] http://arrl.org/the-sun-the-earth-the-ionosphere
[7] http://k9la.us/
[8] https://bit.ly/3Rc8Njt
---
þ Synchronet þ Whiskey Lover's Amateur Radio BBS

11/21/2025

Solar activity has remained low this past week. The largest flare
was a C9.9 on November 19 from a region just beyond the NE limb near
N17. Region 4284 grew slightly in the early part of the period but
was in decay after November 19.

New Region 4287 was numbered. A Type II radio sweep (estimated at
695 km/s) was observed on November 19 at 2215 UTC, likely associated
with a B9.0 flare from just beyond the east limb. No Earth-directed
CMEs were observed. Solar activity is expected to be at low levels,
with slight chance for moderate levels (R1-R2/minor-moderate) to
November 21.
ÿ
Solar wind parameters were at nominal levels. Solar wind speed
ranged from 346 - 421 km/s. Total field ranged from 4-8 nT while the
Bz component was between +8/-2 nT. Phi angle was predominantly
negative. By late November 20, a negative polarity coronal hole high
speed stream (CH HSS) is expected to become geoeffective, causing a
minor enhancement in the solar wind.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere, November 20, 2025, by F. K. Janda, OK1HH:

"Solar activity over the last three months has fluctuated fairly
regularly within an approximately 27-day period, determined by the
rotation of the Sun. The positions of active longitudes do not
change much, which makes it relatively easy to predict not only
solar but also geomagnetic activity. However, we are still close to
the 11-year maximum, so the large solar flares on November 9, 10,
and 11 were not a major surprise.

"However, the fact that the coronal plasma clouds from the first two
flares merged (the second, faster one caught up with the first) and
caused a massive geomagnetic disturbance on November 12 could have
been a surprise.

"The massive disturbance lasted only until November 13, followed by
alternating calm days on November 14-15 and November 18-19 with
turbulent days, for which a more accurate forecast was not possible.
We are likely to see an increase in solar activity during the third
3rd of November and the first 3rd of December, with increased
geomagnetic activity most likely expected in the last days of
November and the first days of December. However, the regularity of fluctuations in solar and geomagnetic activity will end during this
period, while it is advisable to pay attention to newly emerging
active regions and the shift of coronal holes on the Sun."

High Speed Stream activity is expected to wane through November 22.
Solar wind speeds in the 450-550 km/s range are likely based on
recurrent values.ÿ The geomagnetic field is likely to reach
unsettled conditions on November 22 due to waning solar wind
enhancements. Mostly quiet conditions are expected on November 23.

Spaceweather.com[1] for November 21 reports that Sunspot 4274, which
caused the Veteran's Day aurora and radiation storm, will be back
after Thanksgiving.

The latest video report from Dr. Tamitha Skov, WX6SWW, can be found
on YouTube at, https://www.youtube.com/watch?v=FOLDm_N6ft8[2] .

The current Solar Cycle Progression from the NOAA/Space Weather
Prediction Center can be found at, https://www.swpc.noaa.gov/products/solar-cycle-progression[3] .

The Predicted Planetary A Index for November 22 to 28 is 8, 5, 15,
18, 25, 20, and 10, with a mean of 14.4.ÿ Predicted Planetary K
Index is 3, 2, 4, 5, 5, 5, and 3, with a mean of 3.9.
10.7-centimeter flux is 110, 105, 110, 110, 110, 120, and 130, with
a mean of 113.6.

For more information concerning shortwave radio propagation, see http://www.arrl.org/propagation[4] and the ARRL Technical Information
Service web page at, http://arrl.org/propagation-of-rf-signals[5]. For
an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere[6] . Information and
tutorials on propagation can be found at, http://k9la.us/[7] .

Also, check this:

https://bit.ly/3Rc8Njt[8]

"Understanding Solar Indices" from September 2002 QST.

ÿ


[1] http://Spaceweather.com
[2] https://www.youtube.com/watch?v=FOLDm_N6ft8
[3] https://www.swpc.noaa.gov/products/solar-cycle-progression
[4] http://www.arrl.org/propagation
[5] http://arrl.org/propagation-of-rf-signals
[6] http://arrl.org/the-sun-the-earth-the-ionosphere
[7] http://k9la.us/
[8] https://bit.ly/3Rc8Njt
---
þ Synchronet þ Whiskey Lover's Amateur Radio BBS