[SFDXA] ARLP001 Propagation de K7RA

Fri Jan 5 21:17:45 EST 2024

> 
> SB PROP @ ARL $ARLP001
> ARLP001 Propagation de K7RA
> 
> ZCZC AP01
> QST de W1AW  
> Propagation Forecast Bulletin 1  ARLP001
> From Tad Cook, K7RA
> Seattle, WA  January 5, 2024
> To all radio amateurs 
> 
> SB PROP ARL ARLP001
> ARLP001 Propagation de K7RA
> 
> Only four new sunspot groups emerged over the past week, one on
> December 28, another on December 31, and two more on January 2 and
> 3.
> 
> Solar indices sank. The average daily sunspot number declined from
> 114.4 to 63.4, and average daily solar flux from 172.6 to 141.9.
> 
> Average daily planetary A index rose from 8.4 to 6.7 and middle
> latitude numbers from 4 to 5.1.
> 
> Predicted solar flux over the next few weeks is 130 on January 5-7,
> 135 on January 8-10, 140 on January 11, 155 on January 12-14, then
> 160, 165, 160 and 155 on January 15-18, 150 on January 19-21, then
> 145 and 140 on January 22-23, and 135 on January 24-26, 130 and 145
> on January 27-28, 140 on January 29-30, 145 on January 31 through
> February 1, 150 on February 2-4, 155 on February 5-6, 160 on
> February 7, and 155 on February 8-10.
> 
> This is from the Thursday forecast, which looks substantially weaker
> than the Wednesday outlook in Thursday's ARRL Letter.
> 
> Predicted planetary A index is 5, 5, 8, 10 and 8 on January 5-9,
> then 5 on January 10-26, then 8, 15 and 12 on January 27-29, 8 on
> January 30-31, 5 on February 1-3, then 10, 10 and 8 on February 4-6,
> and 5 on February 7-18.
> 
> Solar activity looks soft of late, but perhaps we will see a double
> peak in this cycle.
> 
> But look at this illustration comparing progress in the current
> cycle against the last cycle, month by month since each minimum:
> 
> https://bit.ly/4aMBefh
> 
> Page down to the second chart, labeled "Solar Cycle Comparison."
> 
> There is some confusion because of the similarity in colors.
> 
> The red line is the last cycle, probably smoothed by monthly
> averages.  The blue green line inside it is probably a conventional
> moving average with points on the line smoothed over a year.
> 
> The yellow line is the current cycle, also probably smoothed over a
> year, and the light blue green line is the current cycle, probably
> smoothed with monthly numbers.
> 
> This looks promising for more activity to come.
> 
> Weekly Commentary on the Sun, the Magnetosphere, and the Earth's
> Ionosphere, January 4, 2024, from F.K. Janda, OK1HH.
> 
> "The first celebrations of the end of the calendar year in Western
> civilization are associated with the person of the canonized Pope
> Silvester I, who died on the last day of the year 335. However, no
> one expected that December 31, 2023, would be celebrated with
> fireworks all the way on the Sun.
> 
> "Helioseismological observations focused on a large active region
> approaching the northeastern limb of the solar disk from the far
> side, and large spots on the far side of the Sun were seen by the
> camera of the Perseverance rover on Mars. But no one actually
> expected a proton solar flare, the largest in the current
> eleven-year cycle.
> 
> "The X5.0 eruption in X-ray band 1 to 8 Angstrom occurred at 2155
> UTC in NOAA/SWPC 3536 and was the largest observed eruption since
> the X8.2 eruption on September 10, 2017. In the same sunspot group
> (in the previous solar rotation), an X2.8 eruption was observed on
> December 14, 2023, whereby this was the strongest since the
> beginning of Solar Cycle 25 up to that point.
> 
> "In particular, however, it also contributed to expectations of a
> further increase in activity in the next year or two.
> 
> "Four days later, AR3536 is no longer as large as it was on the
> Sun's far side and about half the size it was in December as AR3514,
> but it is still capable of producing moderate solar flares.  Now AR
> 3536 is approaching the central meridian from where a possible CME
> (within the next week) could already be hitting Earth.  At the same
> time, we expect a further increase in solar radiation , which could
> improve propagation conditions in the DX bands. But of course, also
> worsen if a possible magstorm lasts longer or even starts at night."
> 
> I was on a video session on Sunday with Dr. Tamitha Skov and her
> Patreon subscribers. She was displaying the Sun in real time when
> the big flare happened. It was quite dramatic.
> 
> She was also using a setting on Pskreporter.info that I had never
> tried before. The settings are, "On All Bands, show Signals,
> sent/rcvd by Anyone, using All Modes, over the last" (pick a time).
> 
> In real time we could immediately see the effects the flare had on
> propagation. It was fascinating. I use this regularly now to check
> worldwide propagation on all HF bands.
> 
> I asked her if her husband was an astrophysicist, and she said,
> "No." She yelled, "Hey Kent! Come in here."
> 
> Kent is an actor, an acting coach, a producer, and a writer. I asked
> how they met, which was hilarious. You won't read it here, but you
> can email me if you want more details.
> 
> Scott Craig, WA4TTK years ago built some Windows software that sucks
> up solar data from this bulletin and displays it in a nice format on
> his Solar Data Plotting Utility. To update it, you just create a
> plain .txt file of this bulletin and point the program to the file.
> 
> You can download it from http://www.craigcentral.com/sol.asp and
> also on the same page is an updated data file good through 1/3/2024.
> 
> The latest video from Dr. Tamitha Skov, WX6SWW:
> 
> https://youtu.be/WN4iqCq4LAU
> 
> An article about a powerful solar storm:
> 
> https://bit.ly/3RO0Ek5
> 
> Two articles about a solar storm that will hit hard:
> 
> https://bit.ly/3vqMhL9
> 
> https://bit.ly/41L5SBI
> 
> 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 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 article:
> 
> https://bit.ly/3Rc8Njt
> 
> Instructions for starting or ending email distribution of ARRL
> bulletins are at http://arrl.org/bulletins .
> 
> Sunspot numbers for December 28, 2023, through January 3, 2024, were
> 83, 92, 48, 55, 44, 59, and 63, with a mean of 63.4. 10.7 cm flux
> was 146.7, 142.9, 139.7, 146.2, 135.7, 142.1, and 140.2, with a mean
> of 141.9. Estimated planetary A indices were 3, 6, 5, 4, 10, 8, and
> 11, with a mean of 6.7. Middle latitude A index was 2, 6, 4, 2, 6,
> 8, and 8, with a mean of 5.1.
> NNNN
> /EX