[SFDXA] ARLP030 Propagation de K7RA

[Bill]

> SB PROP @ ARL $ARLP030
> ARLP030 Propagation de K7RA
> 
> ZCZC AP30
> QST de W1AW  
> Propagation Forecast Bulletin 30  ARLP030
> From Tad Cook, K7RA
> Seattle, WA  July 24, 2015
> To all radio amateurs 
> 
> SB PROP ARL ARLP030
> ARLP030 Propagation de K7RA
> 
> All daily sunspot numbers dipped into the double digits last week,
> with the average declining from 73.7 to 43.4. This compares the
> latest July 16 to 22 period against the previous seven days.
> 
> Over the same periods, average daily solar flux went from 114.8 to
> 95.1.
> 
> Geomagnetic indices were mostly quiet, with average daily planetary
> A index going from 13.7 to 6.1 and average mid-latitude A index
> declining from 12.3 to 8.1.
> 
> At 0749 UTC on July 23 the Australian Space Forecast Center posted a
> geomagnetic disturbance warning: "A sustained period of southward
> IMF is resulting in mildly elevated levels of geomagnetic activity,
> particularly at high latitude regions. Further mildly elevated
> levels of geomagnetic activity are possible during the remainder of
> 23 July."
> 
> And indeed the planetary A index for the day was 23, with planetary
> K index reaching 3, 4, 5 and 3 over the first four 3-hour readings.
> The high latitude college A index was 33, with the first K index
> readings at 3, 4, 7, and 4.
> 
> Predicted solar flux is 90 on July 24, 95 on July 25, 100 on July 26
> and 27, 105 on July 28 to 30, 110 on July 31, 115 on August 1 to 4,
> 110 and 105 on August 5 and 6, 100 on August 7 to 9, then 95 on
> August 10 to 13, finally dipping to 85 by August 15, then peaking
> (weakly) at 115 on August 28 to 31.
> 
> Predicted planetary A index is 15, 12, 8 and 5 on July 24 to 27,
> then 10, 8, 5 and 18 on July 28 to 31, then 25 and 12 on August 1
> and 2, 5 on August 3 to 5, then 20, 25, 15, 10, and 8 on August 6 to
> 10, 5 on August 11 to 15, 10 on August 16, 5 on August 17 and 18,
> then 15 and 10 on August 19 and 20, 5 on August 21 to 26, then 18,
> 25 and 12 on August 27 to 29.
> 
> NOAA says the geomagnetic field is expected to be quiet to active on
> July 24 and 25 and quiet to unsettled on July 26.
> 
> OK1HH sees the geomagnetic field as quiet to active on July 24,
> quiet to unsettled July 25, mostly quiet July 26, quiet July 27,
> mostly quiet July 28, quiet July 29, quiet to active July 30, active
> to disturbed July 31 through August 1, quiet to active August 2,
> mostly quiet August 3, quiet on August 4, mostly quiet August 5,
> quiet to active August 6, active to disturbed August 7 and 8, quiet
> to active August 9, quiet to unsettled August 10, mostly quiet
> August 11, quiet August 12 to 14, mostly quiet August 15, quiet to
> unsettled August 16, mostly quiet August 17 and quiet on August 18.
> 
> He sees increases in solar wind on July 24 to 26, August 1 to 5, and
> 8 to 10.  He sees uncertainty though for any predictions on July 26,
> August 1 to 5, August 8, August 17 and 18.
> 
> Here is an interesting article about how the far side views of the
> sun from the STEREO mission are disrupted because the satellite
> transmissions back to earth are blocked by the sun. But here the
> Curiosity rover on Mars fills in.
> 
> http://www.space.com/30012-mars-rover-curiosity-sunspots-far-side.html
> 
> Check this table of predicted International Sunspot Numbers:
> http://1.usa.gov/1HOVlDP
> 
> or:
> 
> ftp://ftp.ngdc.noaa.gov/STP/space-weather/solar-data/solar-indices/sunspot-numbers/predicted/table_international-sunspot-numbers_monthly-predicted.txt
> 
> Note the next minimum is predicted roughly for July 2019, just four
> years from now, and unlike the last minima, there is some sunspot
> activity!  Let's hope this is correct. Compare those numbers with
> all of 2009 in the same table. These are smoothed sunspot numbers,
> and someone out there is optimistic.
> 
> 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/.
> 
> Archives of the NOAA/USAF daily 45 day forecast for solar flux and
> planetary A index are in downloadable spreadsheet format at
> http://bit.ly/1IBXtnG and http://bit.ly/1KQGbRm .
> 
> Click on "Download this file" to download the archive and ignore the
> security warning about file format. Pop-up blockers may suppress
> download. I've had better luck with Firefox than IE.
> 
> 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 16 through 22 were 55, 40, 52, 46, 39, 37,
> and 35, with a mean of 43.4.  10.7 cm flux was 99.6, 97.4, 96, 99.4,
> 93.2, 91, and 89, with a mean of 95.1. Estimated planetary A indices
> were 8, 5, 4, 3, 5, 10, and 8, with a mean of 6.1. Estimated
> mid-latitude A indices were 15, 7, 4, 3, 7, 12, and 9, with a mean
> of 8.1.
> NNNN
> /EX