[SFDXA] ARLP026 Propagation de K7RA

Fri Jun 30 12:52:49 EDT 2023

> 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 at 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