SB PROP @ ARL $ARLP028
ARLP028 Propagation de K7RA

ZCZC AP28
QST de W1AW
Propagation Forecast Bulletin 28 ARLP028
From Tad Cook, K7RA
Seattle, WA July 14, 2023
To all radio amateurs

SB PROP ARL ARLP028
ARLP028 Propagation de K7RA

"GEOMAGNETIC DISTURBANCE WARNING ISSUED AT 0713UT/13 JULY 2023 BY
THE AUSTRALIAN SPACE WEATHER FORECASTING CENTRE.

A glancing CME impact is expected late on 13-July and another CME
impact is expected early on 15-July. These impacts present the
possibility of geomagnetic storm activity over 13-15 July."

We saw a welcome rise in solar activity this reporting week, July
6-12.

Referencing the previous seven days, average daily sunspot numbers
rose from 126.1 to 181.9, while average daily solar flux increased
from 164.5 to 179.4. On July 13 the solar flux was 202.9, well above
the average for the previous seven days.

Geomagnetic indicators did not change much, average planetary A
index going from 7.3 to 8.6 and average daily middle latitude A
index from 8 to 8.1.

The most active day was July 7 when University of Alaska's college A
index was 40. The middle latitude A index on that day was only 11.
The college A index is from a magnetometer in Fairbanks.

What is the outlook for the next month?

Predicted solar flux looks great over the next few days, at 200,
202, 198, 200, and 204 on July 14-18, 202 on July 19-21, 160 on July
22-23, 155 on July 24-25, 160 on July 26-27, 165 on July 28-29, 170
on July 30-31, 165 on August 1-4, 170 on August 5, 175 on August
6-7, 170 on August 8, then 165 on August 9-11, 170 on August 12, 175
on August 13-14, 170 on August 15-17, and 160 on August 18-19.

Predicted planetary A index is 10 on July 14, 5 on July 15 through
August 2, then 10, 8 and 5 on August 3-5, then 8, 8, 5, 8 and 8 on
August 6-10, 5 on August 11 through the end of the month.

On July 12, Spaceweather.com reported:

"A new hyperactive sunspot is producing M-class solar flares every
few hours. This is causing shortwave radio blackouts around all
longitudes of our planet. If current trends continue, an X-flare
could be in the offing."

See Spaceweather.com for updates.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere July 14-20, 2023 from OK1HH.

"Over the past week, we were surprised by two large groups of spots
that appeared on the eastern limb of the solar disk.

The first of these, AR3363, emerged in the southeast. Although it
remained large, there was nothing significant going on. Its opposite
was AR 3372 a few days later, which produced moderate-sized flares
almost daily.

In both cases, helioseismic echoes from the sun's far side suggested
that it may be the leading edge of a large active region.

But there was no indication that these would be areas with a
diametrically different type of activity.

The images of the two groups of spots were large enough to be
observed by the Mars rover Perseverance. Because of Mars' position,
it saw them a few days earlier than a terrestrial observer. For the
record: Perseverance observes the Sun daily, but mainly so that it
can tell from the drop in brightness that a Martian dust storm is
approaching.

AR3372 activity is increasing, while on July 11 and 12 several
M-class solar flares (some with CMEs) have already occurred (X-class
flare appeared to be imminent). In particular, it was almost certain
that the Earth's magnetic field activity would increase in the
following days. The probability of magnetic storms increased
significantly as AR3372 rotated more and more toward the Earth."

Carl, K9LA had comments on the OK1HH report from last week.

"There have been many papers in recent years that have looked at the
trends in ionospheric parameters over the past decades. Although the
changes are small, they do show up in ionosonde data after much math
to eliminate solar activity and geomagnetic field activity. These
results show both positive and negative trends in the F2 region
electron density, likely due to neutral atmosphere dynamics and
electrodynamics that could give regional differences.

An interesting paper in 2008 Geophysical Research Letters modeled
the increased levels of CO2 (global warming) in the atmosphere
versus the impact on the ionosphere.

See: https://bit.ly/3OaThCC

They used 2000 as the baseline with 365 ppmv of CO2, and doubled the
amount of CO2 for the year 2100. Their results showed that electron
densities in the E and F1 region would increase a couple percent in
2100 while the height of the E region peak would decrease a couple
km. In the F2 region, the electron density would decrease by several
percent in 2100 while the height of the F2 region would decrease 10
or so km."

Thanks to reader David Moore for this, on aurora hype:

https://bit.ly/44ovzsh

Flare video (with music.)

https://www.youtube.com/watch?v=aghiHieqCZQ

Huge sunspot: https://bit.ly/44EcqTz

Tamitha Skov reports: https://youtu.be/nwtCBH04bIg

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 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 .

Also, check this article from September, 2002 QST:

https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf

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/

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

Sunspot numbers for July 6 through 12, 2023 were 149, 147, 167, 183,
181, 227, and 219, with a mean of 181.9. 10.7 cm flux was 157.6,
161.4, 160.5, 179.2, 190.6, 213.5, and 193.3, with a mean of 179.4.
Estimated planetary A indices were 11, 18, 8, 4, 5, 8, and 6, with a
mean of 8.6. Middle latitude A index was 11, 16, 6, 4, 6, 8, and 6,
with a mean of 8.1.
NNNN
/EX
--- SBBSecho 3.20-Win32
* Origin: The Thunderbolt BBS - Little Rock, Arkansas (454:1/33)

SB PROP @ ARL $ARLP029
ARLP029 Propagation de K7RA

ZCZC AP29
QST de W1AW
Propagation Forecast Bulletin 29 ARLP029
From Tad Cook, K7RA
Seattle, WA July 21, 2023
To all radio amateurs

SB PROP ARL ARLP029
ARLP029 Propagation de K7RA

Average daily sunspot numbers declined, but average daily solar flux
increased. Sunspot averages were 181.9 last week, and 130.6 this
week. Average daily solar flux increased from 179.4 to 190.5.

Two new sunspot groups emerged on July 14, three more on July 17 and
another two on July 19.

Average daily planetary and middle latitude A index were both 12.9
this week, rising from 8.6 and 8.1.

Predicted solar flux is 185 on July 21-23, then 180, 178, 175 and
170 on July 24-27, 165 on July 28-29, 170 on July 30-31, 165 on
August 1-4, then 170, 175, 175 and 170 on August 5-8, 165 on August
9-11, 170 on August 12, 175 on August 13-14, and 170 on August
15-19, 160 on August 20-23, 165 on August 24-25, then 170 on August
26-27 and 165 on August 28-31.

Predicted planetary A index is 20, 12, 8, 12 and 10 on July 21-25, 5
on July 26 through August 2, then 10 and 8 on August 3-4, 5 on
August 5-14, then 12, 8 and 8 on August 15-17, and 5 on August
18-29.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere for July 20, 2023 from OK1HH.

"We've seen another seven days of mostly moderate solar activity,
with almost daily eruptions of moderate magnitude on the Sun. Some
of these have been the source of CMEs. If the Earth has been
affected by them, a geomagnetic disturbance followed, with a drop in
MUF and a worsening of HF propagation in the process.

As predicted, the expected CME hit the Earth's magnetic field on the
afternoon of 14 July (as part of the Bastille Day celebrations, but
not nearly as strongly as in 2000).

Another CME left the Sun on 14 July, and yet another on July 15.
Because the cloud of later ejected solar plasma was faster, it
cannibalized the previous CME. Together, they hit the Earth on July
18.

But by then AR3363 had already produced a significant long-lasting
M6-class solar flare, and energetic protons accelerated by this
flare reached the Earth and caused a radiation storm. Although MUFs
were quite high, HF conditions were adversely affected by frequent
occurrences of attenuation.

Another CME hit the Earth on 20 July, registered by the Earth's
magnetic field at 1708 UTC.

Further developments were predicted up to G1 to G2 class geomagnetic
storms, with a small probability also of G3, but by then this report
will have been completed and sent out.

Finally, just a little note on the consequences of global change: it
has been manifested in the last eleven-year cycles, in the Earth's
troposphere it is the result of warming, but in the ionosphere it is
rather the opposite. It has been the subject of a number of
scientific papers in recent years.

It is crucial for us, for amateur radio practice, that the current
MUFs are lower than those calculated from sunspot counts for most of
the twentieth century. Therefore, we should input Ri (or solar flux
SFU) into forecast programs lower than what is currently measured
and published.

F.K. Janda, A.R.S. OK1HH http://ok1hh.nagano.cz/ "

News from N8II in West Virginia.

"The bands are in much better shape than most hams realize; activity
levels are normally quite low this summer. In the IARU contest I
observed 15M open to Europe through 0300 UTC and I had QSOs with
Indonesia, China, Nepal, Japan, Central/Western Siberia, Kazakhstan,
and the Philippines in the 2300-0300 UTC period.

I copied GR2HQ (Great Britain HQ station) on 10M CW at 0140 UTC. At
1100 UTC on 15M EU and Central/West Asia were very loud and I
started running a pile up on CW.

The Far East was also in on 15M around 1400 UTC Saturday when I
worked a loud Japanese station.

During the evening/night EU signals were extremely loud on 20M. I
also worked a few EU on 10M 1300-1400 UTC Saturday thanks to
Sporadic E and also caught Z30HQ (Macedonia HQ) on 10M CW Sunday
about 1130 UTC. I worked 697 QSOs concentrating on DX on the high
bands in less than 12 hours with 100 W.

Africa is workable on 10-15M well into our evening as are South
Pacific stations.

Sporadic E this year seems somewhat attenuated, but Es was good from
here and great from the Central/Western USA during the June VHF
contest. I made about 170 CW/SSB QSOs."

CNN presented a smart piece on the sunspot cycle peaking sooner than
expected. https://bit.ly/3rzNJJ6

Double peaked flare. https://bit.ly/46ZoznE

Astronomy club observes sunspots. https://bit.ly/46SaacR

Aurora. https://bit.ly/44FxM2U

Scientific American. https://bit.ly/3rHzGkB

Early peak. https://bit.ly/44Aa7AF https://bit.ly/3rEa0Wj

Cannibal eruption. https://bit.ly/3Q5dv1W

Great video of eruption. https://youtu.be/YOzHHM4B4gA

The latest from Space Weather Woman Dr. Tamitha Skov, WX6SWW.

https://youtu.be/KsKDVOuboyw

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 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 .

Also, check this article from September, 2002 QST:

https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf

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/

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

Sunspot numbers for July 13 through 19, 2023 were 146, 141, 96, 99,
149, 142, and 141, with a mean of 130.6. 10.7 cm flux was 202.9,
180.6, 178.5, 184.3, 180, 218.5, and 188.9, with a mean of 190.5.
Estimated planetary A indices were 7, 20, 8, 10, 24, 16, and 5, with
a mean of 12.9. Middle latitude A index was 9, 17, 9, 13, 19, 16,
and 7, with a mean of 12.9.
NNNN
/EX
--- SBBSecho 3.20-Win32
* Origin: The Thunderbolt BBS - Little Rock, Arkansas (454:1/33)

SB PROP @ ARL $ARLP030
ARLP030 Propagation de K7RA

ZCZC AP30
QST de W1AW
Propagation Forecast Bulletin 30 ARLP030
From Tad Cook, K7RA
Seattle, WA July 28, 2023
To all radio amateurs

SB PROP ARL ARLP030
ARLP030 Propagation de K7RA

Average daily sunspot numbers declined slightly over the past week
(July 20-26) to 128.1, compared to 130.6 over the previous seven
days.

Average daily solar flux declined significantly from 190.5 to 172.2.

The solar flux forecast sees values at 165 and 162 on July 28-29,
158 on July 30-31, then 155 on August 1-3, then 165, 170 and 175 on
August 4-6, 180 on August 7-10, 175 on August 11-13, 180 on August
14-15, 175 on August 16-18, 170 on August 19, then 165, 165 and 160
on August 20-22, and 155 on August 23-26, 160 on August 27, 165 on
August 28-30, 170 and 175 on August 31 through September 1, and 180
on September 2-6.

Predicted planetary A index is 5 on July 28-29, 15 and 10 on July
30-31, 5 on August 1-3, 8 on August 4, 5 on August 5-9, 10 on August
10, 8 on August 11-13, 5 on August 14-19, then 10, 8 and 5 on August
20-22, 12 on August 23-24, 10 on August 25-26, 5 on August 27-29, 10
and 8 on August 30-31, and 5 on September 1-5.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere -- July 27, 2023 from OK1HH.

"The likelihood of more massive solar flares has slowly decreased in
recent days as large groups of spots have fallen behind the western
limb of the solar disk and the magnetic configuration of the
remaining regions has become increasingly simple over the past few
days.

On July 20 and 21, two CMEs struck Earth's magnetic field in
accordance with the prediction. However, both impacts were weak and
did not produce even a minor geomagnetic storm.

Another weak halo CME was expected to leave the Sun on 23 July at
about 1530 UTC in a C5 class flare in spot group AR3376, coinciding
with the outburst of a relatively nearby magnetic filament. The
Earth's magnetic field detected its arrival at 0200 UTC on 26 July.
The result was an increase in geomagnetic activity and a
deterioration of shortwave propagation conditions. The disturbance
actually started on 25 July at 2235 UTC, but it was not clear
whether it was an early arrival of the same CME or another one that
we did not detect.

Note: since I will be abroad next week, I will not post the next
comment on August 3, but on August 10."

Sunspots, flares and aurora. https://bit.ly/44JxcRp

Mars Rover sees the far side of the sun. https://bit.ly/3KbRV8b

Rocket punches hole in ionosphere. https://bit.ly/3KceBFB

Nearly five decades ago I witnessed the same thing, viewed from
Marin County, California. It was a huge dramatic display, My friend
had seen it before, and said it was created by a rocket launch from
Vandenberg AFB in Southern California.

Another CME. https://bit.ly/44LhRjx

On July 27, Spaceweather.com sent this alert:

"A STRONG FARSIDE CME JUST HIT SOLAR ORBITER: Europe's Solar Orbiter
just got hit by the kind of CME that may have once caused a major
power blackout on Earth. This time, Earth was not in the line of
fire. It was a farside eruption that flew away from our planet.
Maybe next time?"

Massive flare? https://bit.ly/3Ya7OSC

Latest from Dr. Tamitha Skov. https://youtu.be/cD5VbWvBXsE

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 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 .

Also, check this article from September, 2002 QST:

https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf

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/

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

Sunspot numbers for July 20 through 26, 2023 were 131, 121, 103,
117, 141, 137, and 147, with a mean of 128.1 10.7 cm flux was
184.3, 172.8, 174.4, 172.5, 165.1, 169, and 167.4, with a mean of
172.2. Estimated planetary A indices were 10, 13, 9, 6, 7, 11, and
21, with a mean of 11. Middle latitude A index was 10, 11, 9, 5, 8,
12, and 23, with a mean of 11.1.
NNNN
/EX
--- SBBSecho 3.20-Win32
* Origin: The Thunderbolt BBS - Little Rock, Arkansas (454:1/33)

SB PROP @ ARL $ARLP027
ARLP027 Propagation de K7RA

ZCZC AP27
QST de W1AW
Propagation Forecast Bulletin 27 ARLP027
From Tad Cook, K7RA
Seattle, WA July 7, 2023
To all radio amateurs

SB PROP ARL ARLP027
ARLP027 Propagation de K7RA

The average daily sunspot number for June, 2023 was the highest in
21 years, according to Spaceweather.com.

From a July 3 email alert from Spaceweather.com:

"SUNSPOT COUNTS HIT A 21-YEAR HIGH: It's official: The average
sunspot number in June 2023 hit a 21-year high. Solar Cycle 25 has
shot past its predecessor, Solar Cycle 24, and may be on pace to
rival some of the stronger cycles of the 20th century."

Could we see another Cycle 19, the biggest in recorded history, even
back before the birth of radio?

Not too long ago, we heard that this cycle should peak in summer
2025. Later that was revised to 2024. Now I am seeing occasional
references to a cycle peak at the end of this year.

From my own records, average daily sunspot numbers for April through
June 2023 were 93.7, 125.8 and 143.9, a nice upward trend.

Some popular news outlets seem confused by the difference between
sunspot number and number of sunspots, and have quoted another
higher average.

Here is the difference. If they are just counting the total number
of sunspots for the month, this is far different from average daily
sunspot numbers. The sunspot number is somewhat subjective, but it
gets ten points for each sunspot group, and one point for each
sunspot in those groups.

But I stand by my numbers. They are all from NOAA and appear at the
end of each bulletin.

But they may be referencing International Sunspot Number, which may
be different from the SESC numbers from NOAA.

Here is an example of confusing sunspot numbers with number of
sunspots: https://bit.ly/3NCQCAl

This one is also confusing, saying there were 163.4 sunspots in
June. https://bit.ly/3PMu6Ym

But what does this mean? It could be either 163 or 164 sunspots,
but not a fractional number, unless it expresses an average. The
minimum sunspot number is 11. This would be one sunspot group
containing one spot. They are always whole, not fractional
integers.

There was one new sunspot region (group) on June 30, three more on
July 1, one more on July 2, another on July 4, and one more on July
5.

Sunspot and solar flux data again this week did not track together.
Average daily sunspot number declined from 170 to 126.1, while
average daily solar flux rose slightly from 160.3 to 164.5.

Geomagnetic indicators were lower, with average daily planetary A
index declining from 10.7 to 7.3, and middle latitude averages from
9.9 to 8.

Predicted solar flux is 155 on July 7, 150 on July 8 to 10, then 155
on July 11, 160 on July 12 to 13, 175 on July 14 to 18, 170 on July
19 to 21, 160 on July 22 and 23, 155 on July 24 and 25, 160 on July
26 and 27, 165 on July 28 and 29, then 170, 170 and 165 on July 30
through August 1, 155 on August 2 to 6, then 160, 165 and 170 on
August 7 to 9, and 175 on August 10 to 14.

Predicted planetary A index is 5, 12 and 8 on July 7 to 9, 5 on July
10 and 11, then 20 and 30 on July 12 and 13, 8 on July 14 to 22, 5
on July 23 to 30, 8 on July 31 through August 1, then 5 on August 2
to 4, 12 and 8 on August 5 and 6, then 5, 20 and 30 on August 7 to
9, and 8 on August 10 to 18.

Note those big numbers are about one solar rotation apart, which is
about 27.5 days.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere for July 6, 2023 from F. K. Janda, OK1HH.

When the current 25th solar cycle began in December 2019, solar
astronomers thought it would be a weak cycle similar to its
immediate predecessor, solar cycle 24. But now we have a twenty-one
year peak. And we expect a continued increase for about two more
years.

The misfortune is that ongoing global changes are reducing the
ionization rate of the ionosphere. Yet the current conditions for
shortwave or decameter wave propagation do not match the amount of
solar activity - they are worse.

But that's not all. Not only is solar cycle 25 likely to rival some
of the more powerful cycles of the 20th century, but we're likely to
see even more powerful solar flares and magnetic storms. History
repeats itself cyclically, and we need only think of the great
Halloween storm of 2003, including the strongest solar flare ever
recorded in X-ray (X45).

The giant sunspot group AR3354 (only about four times smaller than
the giant sunspot group of early September 1859) made its last
appearance on July 2 with an X-class flare. Two days later it
eclipsed.

We won't lose the source of the stronger flares, however - the
growing AR3359, with its Beta-Gamma magnetic configuration, crossed
the central meridian toward active western longitudes on July 6 and
will continue to grow. With its predicted higher activity, we could
see an increase in the Earth's magnetic field activity as early as
the middle of next week.

Tamitha Skov, from July 1. https://youtu.be/HR8mm30oxOQ

Blackout http://bit.ly/46tTRT8 https://bit.ly/3rhbjdz

Stormy weekend? https://bit.ly/3pDrT6R

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 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 .

Also, check this article from September, 2002 QST:

https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf

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/

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

Sunspot numbers for June 29 through July 5, 2023 were 112, 187, 119,
126, 117, 121, and 101, with a mean of 126.1. 10.7 cm flux was
162.2, 158.6, 165.5, 170.2, 173.2, 167.2, and 154.6, with a mean of
164.5. Estimated planetary A indices were 17, 8, 5, 5, 5, 4, and 7,
with a mean of 7.3. Middle latitude A index was 13, 8, 6, 8, 7, 5,
and 9, with a mean of 8.
NNNN
/EX
--- SBBSecho 3.20-Win32
* Origin: The Thunderbolt BBS - Little Rock, Arkansas (454:1/33)