SB PROP @ ARL $ARLP026
ARLP026 Propagation de K7RA

ZCZC AP26
QST de W1AW
Propagation Forecast Bulletin 26 ARLP026

From Tad Cook, K7RA

Seattle, WA June 30, 2023
To all radio amateurs

SB PROP ARL ARLP026
ARLP026 Propagation de K7RA

Space Weather News sent this alert on June 29:

"BIG SUNSPOT ALERT: One of the biggest sunspots in years is directly
facing Earth. AR3354 is 10 times wider than Earth and about 1/3rd
the size of the historical Carrington sunspot. It's so big,
observers in Europe and North America are seeing it naked eye
through the smoke of Canadian wildfires. Earth-directed flares are
likely in the days ahead."

See https://spaceweather.com/ for continuing coverage.

Conditions were favorable over the Field Day weekend, with the
exception of a brief period when the planetary K index rose to 5 on
Saturday night. This is mentioned in the commentary by OK1HH which
follows.

There were five new sunspot groups on June 23, two more on June 24,
another on June 26 and another on June 27.

Average daily sunspot numbers were up, and solar flux was down.

Average daily sunspot number rose from 143 to 170, and average daily
solar flux declined slightly from 165.4 to 160.3.

This is unexpected, because we normally see these values track
together.

Predicted solar flux is 150 on June 30 through July 5, 155 on July
6, 135 on July 7-8, then 145, 155, 160, 165 and 170 on July 9-13,
175 on July 14-18, 170 on July 19-21, then 160, 150, 145, 145, 140
and 135 on July 22-27, then 130 on July 28 through August 1, 135 on
August 2-4, then 145, 155, and 165 on August 5-7. Flux values may
continue to rise to a peak of 175 before mid-August.

Predicted planetary A index is 8, 15 and 10 on June 30 through July
2, 5 on July 3-7, 12 and 8 on July 8-9, 5 on July 10-11, then a
stormy 20 and 30 on July 12-13, 8 on July 14-23, 12 on July 24-25, 8
on July 26-27, 12 on July 28-29, 8 on July 30, 5 on July 31 through
August 3, 12 and 8 on August 4-5, 5 on August 6-7, then 20 and 30
again on August 8-9. Note that recurring stormy conditions are
predicted at one solar rotation, which is about 27.5 days, following
the July 12-13 prediction.

The above predictions are from forecasters Thompson and Kiser at the
USAF space weather group.

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
Ionosphere June 30 to July 06, 2023 from F.K. Janda OK1HH.

"In the solar X-ray field during June we could observe the most
significant solar flare so far: X1 in the active region AR3341. It
happened on June 20 at 1709 UTC near the southeastern limb of the
solar disk. In the region where the Sun was high, it caused the
Dellinger Effect, https://bit.ly/3NA61kT .

"The same sunspot group was also the source of the M4.8 flare two
days later. It ejected a CME, but not toward Earth.

"Nevertheless, its passage close to Earth probably caused an
increase in geomagnetic activity on the evening of 24 June.
Theoretically, it could also have been a CME from the X1 eruption of
20 June.

"On June 26, we were surprised by sunspot group AR3354 just above
the solar equator and east of the central meridian. It did not exist
the day prior. Over the next two days its area grew to ten times the
size of the Earth, making it easily observable by the naked eye.

"Significantly, its magnetic configuration changed to
beta-gamma-delta, which is enough energy for powerful solar flares.

"The geomagnetic field has been quiet to unsettled so far.

"AR3354 will be pointed directly toward Earth in the next few days,
so it looks like the next disturbance could begin on July 1. And of
course, a possible large flare could cause a Dellinger Effect
throughout the whole HF spectrum."

Pat, W5THT wrote:

"I have been an active ham since 1956 and on the Mississippi coast
since 1971. This year has strengthened my belief in an old
observation.

"There is/was a dome of high pressure that moved from over Texas to
now over me. Before it moved east, I was able to take part in the 6
meter propagation to Europe.

"Since it moved over me, the DX Maps page shows a gap in the DX
propagation from northern Florida to central Louisiana. This is not
the first time I have seen it happen, but the new generation of TV
weather persons presented a picture of the dome of high pressure
that coincided with my propagation observations. Suspicions
confirmed?

"Years ago, on 2 meters I noticed that propagation followed weather
fronts up the east coast. Thanks for reading this and perhaps
someone younger than me has already done the research."

Jon Jones, N0JK wrote:

"Wow -- a surprise opening on 6 meter FT8 to Brazil June 25!

"A CME impact at 1900 UTC may have boosted the TEP MUF Sunday
afternoon. That and some help with sporadic-E -- opening to Brazil
on 6 meters from North America during the summer.

"Had been out with our dog. Saw WQ0P PSK flags for PY2XB. Turned on
radio at home with dipole. PY2XB was loud. Really loud. Also copied
PY5CC. He spotted me as well, but no QSO. PY2XB in for almost half
an hour. Like a pipeline. Saw him work a few 5s and 0s. KC0CF worked
CE2SV. With higher solar activity, the TEP zone still works even in
our summer. This mode works for D2UY (Angola), 3B9FR (Rodrigues
Island in Indian Ocean), and ZL."

An article on Solar Cycle 25 peak and nice images:

https://bit.ly/3ps6iOI

Understanding Space Weather: A Glossary of Terms:

https://bit.ly/3XuimeQ

"Astro Bob" on that big sunspot:

https://bit.ly/46rC3YU

Frequent contributor David Moore shared this fascinating article
comparing the current big sunspot with the one that launched the
infamous Carrington Event 164 years ago.

https://bit.ly/3CUGZYC

Another Solar Cycle article:

https://bit.ly/3XvIk1y

Yet another Carrington Event article:

https://bit.ly/3XuSe3o

Article about Solar max:

https://bit.ly/44jM5tP

A Houston Chronicle article on solar max:

https://bit.ly/445vtWf

Flares and how they are measured:

https://bit.ly/3prvtRs

A video from Dr. Tamitha Skov, WX6SWW, from last week:

https://www.youtube.com/watch?v=sfXz9nk6NDs

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 22 through 28, 2023 were 176, 194, 200,
180, 158, 141, and 141, with a mean of 170. 10.7 cm flux was 173.2,
169.7, 160.8, 154.8, 157.7, 151.2, and 154.9, with a mean of 160.3.
Estimated planetary A indices were 8, 9, 16, 15, 11, 8, and 8, with
a mean of 10.7. Middle latitude A index was 8, 9, 16, 10, 11, 7, and
8, with a mean of 9.9.
NNNN
/EX


--- MBSE BBS v1.0.8 (Linux-x86_64)
* Origin: American Radio Relay League (3:633/280.2@fidonet)

SB PROP @ ARL $ARLP026
ARLP026 Propagation de K7RA

ZCZC AP26
QST de W1AW
Propagation Forecast Bulletin 26 ARLP026

From Tad Cook, K7RA

Seattle, WA July 12, 2024
To all radio amateurs

SB PROP ARL ARLP026
ARLP026 Propagation de K7RA

New sunspot groups, nine in all, emerged on every day of this reporting week, July 4 to 10. One on July 4, another on July 5, two more on July 6, another each on July 7 and July 8, two more on July 9 and another on July 10.

On July 11, two more sunspot groups emerged, and the total sunspot area expanded by 13 per cent.

Despite the appearance of so many new sunspots, average daily sunspot number declined from 181.6 to 129, compared to the previous week. Average daily solar flux barely moved, changing from 175 to 176.6.

Predicted solar flux for the next month is 205 on July 12 and 13, 210 on July 14 and 15, 205 on July 16 to 18, 195 on July 19 and 20, 200 on July 21 to 25, 190 on July 26, 180 on July 27 to 29, 175 on July 30, and 170 on July 31 through August 2, then 165 on August 3 to 6, 160 on August 7 and 8, 175 on August 9, 180 on August 10 to 13, 195 on August 14 to 16, and 200 on August 17 to 21.

Predicted planetary A index is 8, 15, 18, 12 and 8 on July 12 to 16, 5 on July 17 to 20, then 10 and 8 on July 21 and 22, then 5 on July 23 to August 3, then 12, 10, and 5 on August 4 to 6, then 12, 8 and 5 on August 7 to 9, then 12, 10 and 8 on August 10 to 12, then 5 on August 13 to 15, and 10 and 8 on August 16 and 17 and 5 on August 18 and beyond.

Tamitha Skov wrote in an email on Wednesday:

We have a new big flare player rotating through the Earth-strike zone with some X-flare potential. Region 3738 has been growing rapidly over the past 24 hours, with some new spot clusters emerging right in the center of the original set. This kind of growth is highly magnetically unstable and is upping the noise on the day-side radio bands.

As of earlier today, we had already popped a couple of low-level M-class flares and now are approaching the R1-radio blackout level for a noise floor. That is quick growth! I did my best to estimate the conditions for the coming week in these 5-day Outlooks, but in the time it has taken to generate them, the region's growth has accelerated.

It looks like I will need to update the Solar Flare and Day side Radio Blackout Outlook in the above snapshot to something closer to a 60 per cent chance of M-Class flares and a 15 per cent chance of X-class flares. I will do this asap!

Other than Region 3738, we do have a pocket of fast solar wind coming that could give us a decent chance of aurora at high latitudes over the early part of the weekend. This is the only solar storm possibility for now, although we could see a new Earth-directed solar storm launch over the next few days! I will go over this possibility and the new fireworks from Region 3738 in the upcoming forecast I am shooting now.

Dr. Tamitha Skov has many videos of interest to our readers. You can find them here: https://www.youtube.com/c/TamithaSkov [ https://www.youtube.com/c/TamithaSkov ]

Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere, July 11, 2024 from F. K. Janda, OK1HH.

In early July, a sunspot group responsible for the May 10 superstorm reappeared on the southeastern limb. By the way, this superstorm caused thousands of satellites to drop in altitude, according to a research paper just accepted by the Journal of Spacecraft and Rockets.

The aforementioned group was designated AR3664 at the time, in subsequent solar rotations AR3697, AR3723, is visible again, while in the same region are now AR3742, AR3743, and AR3745.

The most active is the rapidly growing AR3768, five times the size of the Earth. Most importantly, there is a coronal hole to the north of AR3768. Between mentioned CH and AR we can expect a source of enhanced solar wind that will very likely head towards the Earth and cause a geomagnetic disturbance on July 13 and 14. Ionospheric shortwave propagation conditions, randomly influenced by sporadic layer E in the northern hemisphere of the Earth during the summer, affected by numerous solar flares will develop, but less regularly.

Cycles 24 and 25 compared: https://bit.ly/3Y05gIM [ https://bit.ly/3Y05gIM ]

Sunspot number calculations and the peak of the cycle: https://yhoo.it/3WjX5Wg [ https://yhoo.it/3WjX5Wg ]

Five flares: https://bit.ly/3WlwuqT [ https://bit.ly/3WlwuqT ]

David Moore sent this about solar convection:
https://bit.ly/3WlQCKF [ https://bit.ly/3WlQCKF ]

Solar max: https://bit.ly/3xK36lR [ https://bit.ly/3xK36lR ]

New look at Maunder minima: https://bit.ly/3WgVoJh [ https://bit.ly/3WgVoJh ]

Send your tips, reports, observations, questions and comments to k7ra@arrl.net [ mailto: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 [ http://www.arrl.org/propagation ] and the ARRL Technical Information Service web page at, http://arrl.org/propagation-of-rf-signals [ 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 [ http://arrl.org/the-sun-the-earth-the-ionosphere ] .

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

Also, check this: https://bit.ly/3Rc8Njt [ https://bit.ly/3Rc8Njt ]

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

Sunspot numbers for July 4 through 10 2024 were 113, 111, 132, 119, 95, 143, and 190, with a mean of 129. 10.7 cm flux was 173, 165.6, 166, 171.3, 168.5, 178.2, and 213.6, with a mean of 176.6. Estimated planetary A indices were 10, 8, 3, 8, 10, 6, and 6, with a mean of 7.3. Middle latitude A Index was 10, 10, 4, 7, 11, 8, and 8, with a mean of 8.3.
NNNN
/EX

ARRL The National Association for Amateur Radio®
Unsubscribe [ http://arrl.informz.net/arrl/pages/Copy_of_Copy_of_Unsubscribe_Test_GF?_zs=KTqxl&_zmi=KOmF ]


--- MBSE BBS v1.0.8.4 (Linux-x86_64)
* Origin: American Radio Relay League (3:633/280.2@fidonet)