[SFDXA] ARLP032 Propagation de K7RA

[William Marx]

> SB PROP @ ARL $ARLP032
> ARLP032 Propagation de K7RA
> 
> ZCZC AP32
> QST de W1AW  
> Propagation Forecast Bulletin 32  ARLP032
> From Tad Cook, K7RA
> Seattle, WA  August 5, 2016
> To all radio amateurs 
> 
> SB PROP ARL ARLP032
> ARLP032 Propagation de K7RA
> 
> Average daily sunspot numbers dropped from 19.3 last week to 10.7 in
> the current reporting week, July 28 through August 3. Average daily
> solar flux declined from 82.5 to 72.1.
> 
> Geomagnetic indices were more active this week, with average daily
> planetary A index increasing from 8.7 to 13, and mid-latitude A
> index rising from 8.9 to 11.9.
> 
> Sunspot numbers were low all week, and on Wednesday August 3 the
> sunspot number dropped to 0, as in no sunspots. And there were still
> no sunspots the next day, August 4.
> 
> Predicted solar flux is 80 on August 5-7, then 85, 90 and 95 on
> August 8-10, 100 on August 11-12, 95 on August 13-15, 90 on August
> 16-17, then 85 and 80 on August 18-19, 75 on August 20-22, 70 on
> August 23-27, 72 on August 28-30, 75 on August 31, 85 on September
> 1, 90 on September 2-3, then 95 on September 4-11 and 90 on
> September 12-13.
> 
> Predicted planetary A index is 15 on August 5-6, then 10, 20, 8, 12,
> 10 and 8 on August 7-12, 5 on August 13-14, 12 on August 15-16, 5 on
> August 17, 8 on August 18-19, 5 on August 20-23, 15 on August 24-25,
> 5 on August 26-27, 8 on August 28, 20 on August 29-30, 15 on August
> 31, 12 on September 1, 10 on September 2-3, then 8 and 5 on
> September 4-5, 12 on September 6-7, 8 on September 8, 5 on September
> 9-10 and 12 on September 11-12.
> 
> Geomagnetic activity forecast for the period August 5-August 31,
> 2016 from OK1HH of the Czech Propagation Interest Group.
> 
> Geomagnetic field will be:
> Quiet on August 13-14, 23, 27-28
> Mostly quiet on August 22
> Quiet to unsettled on August 5, 9, 11-12, 15, 18, 24, 31
> Quiet to active on August 6, 10, 20, 25-26, 30
> Active to disturbed on August 7-8, (16-17, 21,) 29
> 
> Increasing solar wind from coronal holes are expected on August 5-8
> (- 9), 14, 22-23, 29-30
> 
> Parenthesis means lower probability of activity enhancement.
> 
> "The Times of India" has an article on solar flares at,
> http://bit.ly/2aCj0Sn .
> 
> Howard Schler, K2EQ of Ovid, New York wrote:
> 
> "I wanted to point out one oddity of propagation that has been
> occurring on a daily basis for many weeks though now a bit less.
> 
> "On 20 Meters, each day between midnight local time 0500z to about
> 0630z or 0700z, PSK is almost completely dead, less than a handful
> of stations and most very weak and broken up.
> 
> "However, the surprising exception is that in the midst of that I
> have been able to work VKs, ZLs and other South Pacific stations
> from my home in New York with good to excellent signals, sometimes
> 10,000 miles away and the only signal on the PSK spectrum.  We both
> marvel at the propagation and how odd it is yet how strong our
> signals are.  I do not understand propagation beyond a very
> fundamental level.  Nonetheless, there it is and I'm up way past my
> bedtime almost every night calling into a blank noisy band, with
> surprising results."
> 
> Often when a band seems dead, you can call CQ and find out there is
> good propagation, but you haven't heard anyone calling, so it seems
> like there is no propagation.
> 
> Around that time from your place to ZL on 20 meters should be an
> excellent path, according to some path projections I ran with
> W6ELprop.
> 
> Looks like the path opens up about 0230 UTC, and an hour later is
> about 5 dB better. Signals slowly climb til 0530, then level off,
> and then start to fade after 0700. But on some days there could be
> strong signals til 1130 UTC.
> 
> Time to look at our 3 month moving average of sunspot numbers, now
> that July is over. The moving average ending in January through July
> was 55.4, 53.5, 49, 45.3, 43.1, 35.4 and 33. Looks like a steady
> decline in solar activity, although I am surprised to see so many
> zero sunspot days at this point in the declining cycle.
> 
> If you would like to make a comment or have a tip for our readers,
> email the author at k7ra at arrl.net.
> 
> For more information concerning radio propagation, see the ARRL
> Technical Information Service web page at,
> http://arrl.org/propagation-of-rf-signals. For an explanation of the
> 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/.
> 
> Monthly propagation charts between four USA regions and twelve
> overseas locations are at http://arrl.org/propagation.
> 
> Instructions for starting or ending email distribution of ARRL
> bulletins are at http://arrl.org/bulletins.
> 
> Sunspot numbers for July 28 through August 3 were 13, 13, 13, 12,
> 13, 11, and 0, with a mean of 10.7. 10.7 cm flux was 70.3, 70.5, 71,
> 71.5, 71.9, 74.9, and 74.8, with a mean of 72.1. Estimated planetary
> A indices were 15, 14, 6, 3, 3, 17, and 33, with a mean of 13.
> Estimated mid-latitude A indices were 13, 16, 7, 2, 4, 17, and 24
> with a mean of 11.9.
> NNNN
> /EX