[SFDXA] ARLP031 Propagation de K7RA

[WILLIAM MARX]

> SB PROP @ ARL $ARLP031
> ARLP031 Propagation de K7RA
> 
> ZCZC AP31
> QST de W1AW  
> Propagation Forecast Bulletin 31  ARLP031
> From Tad Cook, K7RA
> Seattle, WA  July 30, 2021
> To all radio amateurs 
> 
> SB PROP ARL ARLP031
> ARLP031 Propagation de K7RA
> 
> Solar activity slowed this week.  Average daily sunspot number
> declined to 33.9 this week (July 22 to 28) from 48.9 in last week's
> report.  Wednesday July 28 had no sunspots at all.
> 
> Average daily solar flux went from 81.3 to 83.
> 
> Geomagnetic indicators held steady, with average daily planetary A
> index at 6.4 both last week and this week.  Average daily middle
> latitude A index went from 6.4 last week to 6.3 this week.
> 
> Predicted solar flux is 76 on July 30 and 31, then 74 on August 1,
> 72 on August 2 to 4, 74 on August 5 and 6, 75 on August 7 to 12,
> then 78, 80, 82 and 85 on August 13 to 16, 90 on August 17 and 18,
> 85 on August 19 and 20, 80 on August 21, 82 on August 22 to 28, 78
> on August 29, and 75 on August 30 to September 8.
> 
> Predicted planetary A index is 8, 12 and 8 on July 30 through August
> 1, 5 on August 2 to 9, 12 and 10 on August 10 and 11, 5 on August 12
> to 15, 10 and 8 on August 16 and 17, 5 on August 18 to 23, then 12,
> 12 and 8 on August 24 to 26, 5 on August 27 and 28, 8 on August 29,
> and 5 on August 30 through September 5.
> 
> F. K. Janda, OK1HH is on vacation this week hiking in the mountains
> of the Czech Republic, so we have forecasts from two of his
> associates.
> 
> "Solar activity forecast for the period July 30 to August 05, 2021
> 
> Activity level is mostly very low
> X-ray background flux (1.0 to 8.0 A) in the range A5.5 to B1.5
> Radio flux (10.7 cm) a fluctuation in the range 74 to 82
> Events: class C (0 to 4/period), class M (0/period), class X
> (0/period), proton (0/period)
> 
> Relative sunspot number (Ri) in the range 0 to 55"
> 
> "Geomagnetic activity forecast for the period July 30 to August 05,
> 2021
> 
> Quiet on Jul 30 and 31, Aug 2 to 4
> Unsettled on Jul 31, Aug 1 to 3, 5
> No Active days 
> No Minor storms
> No Major storms
> No Severe storms
> 
> Geomagnetic activity summary:
> 
> Next week, we expect at most quiet to unsettled conditions.  The
> more unsettled events are possible about August 1 and 2, and also
> about Thursday, August 5.
> 
> The other days, we expect quiet to unsettled conditions generally,
> closer to quiet level."
> 
> KC0V wrote:
> 
> "There was a big 2m Es opening from DN70 to the Midwest this
> afternoon, July 24.  I was busy with some chores then happened to
> look at DXMaps and the APRS VHF propagation map and noticed a large
> Es cloud located over eastern NE/western IA and another located over
> SE KS.  I quickly tuned into 2m FT8 144.174.  Signals were very
> strong, with +21 db the best report I sent and +29 the best
> report I received.  My QSOs, beginning at 2216z and ending at 2235
> UTC were as follows:
> 
> WA9DU EM69
> WB8ART EM79
> AA9JS EN51
> KC9IKB EM69
> KA9CFD EN40
> WA4CQG EM72
> KX9X EN50
> NY1V EM69
> KM8V EN91
> K2DRH EN41
> AG4V EM55
> KO9A EN52
> WB8JCW EN80
> 
> Then followed 26 minutes of a mixture of single decodes, total
> quiet, meteor bursts, but no QSOs.  Then at 2301 UTC:
> 
> K9YK EN60
> 
> And then it was over.  I don't know when the opening began since it
> was well and truly in progress when I got to the radio, but it was
> an amazing 20 minutes or so.
> 
> Unfortunately I was unable to complete with W3IP in FM19, which
> would have been the longest distance QSO of the opening for me.  We
> heard each other over several sequences but were unable to finish
> the exchange.
> 
> My station: Kenwood TS-2000, Beko HLV-1000 running at 750W, 10
> element LFA (by G0KSC) at 35 feet.
> 
> 73 - Jan, KC0V"
> 
> 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.
> 
> 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 July 22 through 28, 2021 were 77, 46, 35, 24,
> 25, 25, and 0, with a mean of 33.1.  10.7 cm flux was 89, 87.4 83.9,
> 81.6, 80.8, 79.6, and 78.8, with a mean of 83.  Estimated planetary
> A indices were 11, 4, 4, 3, 4, 6, and 13, with a mean of 6.4.
> Middle latitude A index was 9, 3, 5, 5, 3, 6, and 13, with a mean of
> 6.3.
> NNNN
> /EX