[SFDXA] ARLP013 Propagation de K7RA

[Bill]

> SB PROP @ ARL $ARLP013
> ARLP013 Propagation de K7RA
> 
> ZCZC AP13
> QST de W1AW  
> Propagation Forecast Bulletin 13  ARLP013
> From Tad Cook, K7RA
> Seattle, WA  March 27, 2015
> To all radio amateurs 
> 
> SB PROP ARL ARLP013
> ARLP013 Propagation de K7RA
> 
> Sunspot numbers and solar flux both rose this week. Average daily
> sunspot numbers from March 19 to 25 were up 24.8 points to 83.9,
> compared to the previous seven day period. Average daily solar flux
> rose from 117.5 to 122.4.
> 
> Average planetary A index dropped from 29.4 to 19.4, although
> conditions continued to be active. March 22 and 23 had planetary A
> index numbers at 24 and 21, but there was nothing like the number
> 117 on March 17, a huge, huge level for the A index.
> 
> We saw one new sunspot region on March 19, two on March 21, three on
> March 22 and three more on March 23, another new one on March 24 and
> yet another two days later on Thursday, March 26.
> 
> Predicted solar flux is 135 on March 27 to 30, 145 on March 31 and
> April 1, 140 on April 2 and 3, 130 on April 4 and 5, 125 on April 6
> to 8, 120 on April 9 and 10, 115 on April 11 to 19, 120 on April 20,
> 115 on April 21, 120 on April 22 and 23, and 125 on April 24 to 27.
> 
> The forecast for the next few days changed dramatically from
> Wednesday night's flux prediction, which had flux values at 150 on
> March 27 and 28, 145 on March 29 and 30 and ran in the ARRL Letter.
> As of Thursday night (March 26) the predicted value for all four of
> those days sank to 135.
> 
> On March 25 the predicted planetary A index for March 26 was 8,
> which turned out to be precisely correct. The latest A index
> prediction shows 15 on March 27, 25 on March 28 and 29, then 15, 10
> and 5 on March 30 through April 1, 12 on April 2 to 4, 5 on April 5
> and 6, 8 on April 7 and 8, 5 on April 9 to 11, then 15 and 30 on
> April 12 and 13, 20 on April 14 to 16, 15 on April 17, 20 on April
> 18 and 19, then 12, 5 and 15 on April 20 to 22, and 25 on April 23
> and 24.
> 
> Petr Kolman, OK1MGW of the Czech Propagation Interest Group,
> predicts geomagnetic conditions should be quiet to unsettled March
> 27, active to disturbed March 28 and 29, quiet to unsettled March 30
> through April 2, quiet to active April 3, quiet to unsettled April 4
> and 5, quiet on April 6, mostly quiet April 7 to 10, quiet to
> unsettled April 11 and 12, active to disturbed April 13 to 16, quiet
> to unsettled April 17, quiet to active April 18 and 19, and mostly
> quiet April 20 to 22.  You can see that the geomagnetic conditions
> are all over the place, with many active periods. This is typical
> after the solar cycle passes its peak, which for cycle 24 was about
> a year ago. You can see the peaks in the smoothed (averaged over a
> whole year) sunspot numbers and solar flux in tabular form on pages
> 14 and 15 at http://legacy-www.swpc.noaa.gov/weekly/pdf/prf2062.pdf 
> It looks like sunspot numbers peaked around March through May 2014
> and solar flux around May through July of the same year.
> 
> The word "Legacy" in the above URL reminds us that these weekly
> publications are moving to ftp://ftp.swpc.noaa.gov/pub/warehouse/
> where you select the year of interest (in this case 2015, of course)
> in the folder names toward the bottom of the page, then the
> WeeklyPDF folder. 2015 began with prf2053.
> 
> John Burgoon, KC9TUI of Bloomington, Indiana wrote about his trip to
> Florida, which coincided with the huge geomagnetic upsets of over a
> week ago.
> 
> On March 23, John wrote, "Last week I went on vacation to Amelia
> Island, Florida, happily toting my new 17 meter mobile home brew
> system.  I had a carefully tuned dipole and a single vertical whip.
> By the time we drove down, settled in, and finally got to the point
> that I could set up on the beach, I could not hear much at all. On
> Monday morning I heard a few signals, but no contacts. On Tuesday
> March 17th all I heard was the background hiss of my radio. I set up
> again on Thursday afternoon (19th) and again did not hear anyone.
> Not a single contact. That's the breaks sometimes.
> 
> Next time I'll have more equipment, as I am currently building
> radios for 40 meters, 20 meters, and 10 meters."
> 
> Check out John's bio on QRZ.com, and see what he is doing lately
> with his homebrew projects.
> 
> Don't forget, the CQ World Wide WPX SSB Contest is this weekend,
> March 28 and 29, and the CW weekend is the last weekend in April.
> The cool thing about this contest is that every prefix worked is a
> multiplier. So if your call begins with KQ4, that is a separate
> multiplier from a call starting with WS1. You may have a rare
> prefix, or even a unique one in the contest, making you sought after
> like DX even though you are right here at home in the United States.
> 
> See http://www.cqwpx.com/ for details.
> 
> For more information concerning radio propagation, see the ARRL
> Technical Information Service 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 March 19 through 25 were 71, 27, 40, 88, 119,
> 127, and 115, with a mean of 83.9. 10.7 cm flux was 109.3, 112.7,
> 113.6, 122.4, 128.1, 133, and 137.8, with a mean of 122.4. Estimated
> planetary A indices were 28, 24, 14, 24, 21, 12, and 13, with a mean
> of 19.4.  Estimated mid-latitude A indices were 19, 18, 12, 16, 16,
> 9, and 10, with a mean of 14.3.
> NNNN
> /EX