[SFDXA] ARLP036 Propagation de K7RA

[Bill]

> SB PROP @ ARL $ARLP036
> ARLP036 Propagation de K7RA
> 
> ZCZC AP36
> QST de W1AW  
> Propagation Forecast Bulletin 36  ARLP036
> From Tad Cook, K7RA
> Seattle, WA  September 4, 2020
> To all radio amateurs 
> 
> SB PROP ARL ARLP036
> ARLP036 Propagation de K7RA
> 
> I goofed last week and did not attribute that wonderful narrative
> about solar cycle 19, which was written by Bill Hawkins, W5EC, who
> is currently at the top of the DXCC Honor Roll.
> 
> As of Thursday night, no sunspots have appeared for the past 13
> days.  I know we are all hoping for more sunspots, which I am sure
> will return soon.  I have no special knowledge, but the trends for
> this newly awakening solar cycle seem to favor it.  One event to
> look forward to this month is the autumnal equinox on Tuesday,
> September 22, which should favor worldwide HF propagation.
> 
> Average daily solar flux declined this reporting week (August 27
> through September 2) from 70.4 to 69.6.
> 
> Geomagnetic indicators showed quite a bit more activity than they
> have in some time now.  Average daily planetary A index rose from
> 5.1 to 13.1.  The most active day was August 31, when the planetary
> A index reached 26.  The cause was a vigorous solar wind spewing
> from holes in the solar corona.
> 
> Predicted solar flux is 70, forecast for every one of the next 45
> days.  Predicted planetary A index is 5 on September 4 to 17, 8 on
> September 18 and 19, 5 on September 20 to 22, then 8, 10 and 14 on
> September 23 to 25, 10 on September 26 and 27, then 12 and 10 on
> September 28 and 29, then 5 on September 30 through October 18.
> 
> This article says the solar minimum most likely occurred last
> December:
> 
> http://www.sidc.be/silso/node/166 
> 
> F. K. Janda, OK1HH has returned from vacation with his geomagnetic
> activity forecast for the period September 4 to 29, 2020.
> 
> "Geomagnetic field will be 
> Quiet on:  September 5 to 8, 10 to 13, 16 and 17, 20 and 21 
> Quiet to unsettled on:  September 4, 9, 14, 29 
> Quiet to active on:  September 15, 18 and 19, 22 to 24, 26 
> Unsettled to active:  September 25, 27 and 28 
> Active to disturbed:  Not expected 
> 
> Solar wind will intensify on:  September (4, 15, 19,) 22 and 23 
> 
> Parenthesis means lower probability of activity enhancement."
> 
> OK1HH wrote to us about his river cruise:
> 
> "As a captain, I sailed on the M / Y 'Daisy' (LOA 8 meters, 0.4
> tons) on the Czech rivers Elbe and Vltava on the route Melnik -
> Zernoseky Lake, Usti, Melnik, Luzec, Melnik, a total of 217.4 km.
> And it was a beautiful week!"
> 
> https://pujcovna-plavidel.cz/wp-content/uploads/2018/12/IMAG1260-1-min.jpg
> 
> Thanks to K9LA for this link to a fascinating and informative RSGB
> lecture about sporadic-e propagation:
> 
> https://youtu.be/wn5as91ndG4
> 
> An article about Europe's most powerful solar telescope:
> 
> https://bit.ly/2ETMA75
> 
> Tamitha Skov has a new video:
> 
> https://youtu.be/bTkkmrhxMfU
> 
> I love Dr. Skov's enthusiasm: "Whamo!"  And also of course her
> expertise, which she shares so generously.
> 
> For more information concerning 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.
> 
> 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 August 27 through September 2, 2020 were 0, 0,
> 0, 0, 0, 0, and 0, with a mean of 0.  10.7 cm flux was 70, 70.1,
> 70.2, 70, 69.2, 69.5, and 68.3, with a mean of 69.6.  Estimated
> planetary A indices were 8, 10, 14, 9, 26, 16, and 9, with a mean of
> 13.1.  Middle latitude A index was 7, 8, 14, 8, 19, 16, and 8, with
> a mean of 11.4.
> NNNN
> /EX