SB PROP @ ARL $ARLP031   
   ARLP031 Propagation de K7RA   
      
   ZCZC AP31   
   QST de W1AW   
   Propagation Forecast Bulletin 31  ARLP031   
   > From Tad Cook, K7RA   
   Seattle, WA  August 1, 2014   
   To all radio amateurs   
      
   SB PROP ARL ARLP031   
   ARLP031 Propagation de K7RA   
      
   Spaceweather.com reports that a CME is coming toward us from the sun   
   since July 30 when a magnetic filament erupted. It may sideswipe our   
   magnetic field on Saturday, August 2, and there is a thirty percent   
   chance of geomagnetic storms in polar regions.   
      
   Right now there are plenty of sunspots, but they are magnetically   
   weak.   
      
   Since July 24, the Dominion Radio Astrophysical Observatory in   
   Penticton, British Columbia has been experiencing some serious   
   computer network issues, I think involving a severed fiber optic   
   cable. As a result, we do not have a source for the 10.7 cm. solar   
   flux values resolved to one-tenth of a point. This is not a serious   
   problem, except those of us who archive the values like to see the   
   values in a consistent format. We can still get the flux values   
   resolved to whole integers from NOAA:   
      
   http://www.swpc.noaa.gov/ftpdir/latest/DSD.txt   
      
   These numbers appear at the end of the weekly bulletin. For those   
   who archive the values, when the Penticton site goes back online you   
   will be able to correct the values from these usual sources:   
      
   http://www.spaceweather.ca/solarflux/sx-5-flux-eng.php   
      
   ftp://ftp.geolab.nrcan.gc.ca/data/solar_flux/daily_flux_values/fluxtable.txt   
      
   The official flux number is the daily local noon value, which is at   
   2000 UTC. When the system comes back online, you should see solar   
   flux readings after July 23. NOAA has always presented these as   
   whole integers, and for the past week the noon flux has been   
   supplied via a daily phone call to Boulder from Penticton.   
      
   Using the flux values rounded to whole integers makes little   
   difference. For example, rounding to whole integers would change the   
   average solar flux in ARLP027 from 129.5 to 129.6, and in ARLP028 it   
   does not change the average at all.   
      
   Thank goodness there were no zero-sunspot days over the past week,   
   so the average daily sunspot number rose from 25.9 in the July 17 to   
   23 period to 107.7 this week. Average daily solar flux rose from   
   90.3 to a more robust 125. Solar flux on Thursday, July 31 was 156.   
      
   July ended yesterday, so we can look at recent averages. The average   
   daily sunspot number for July was 113.6, up from 107.8 for June. The   
   three month moving averages of daily sunspot numbers for the past   
   year are 85.6, 77.4, 91.2, 102.9, 123.7, 123.3, 138.5, 146.4, 148.2,   
   129.6, 118.4 and 112.8.   
      
   Predicted solar flux for the near term is 160 on August 1 and 2, 150   
   on August 3, 145 on August 4 to 6, then 140, 120, 110, 105, 100 and   
   95 on August 7 to 12, 90 on August 13 to 15, 95 on August 16 and 17,   
   100 on August 18, and 105 on August 19 to 21.   
      
   > From July 21 to 27 the flux value predicted for August 18 was only   
   85, but that was revised back to 100 on July 28, the same value   
   predicted from July 13 to 20 (for August 18. Is that clear as mud?)   
      
   Predicted planetary A index is 5, 8, 14, 10, and 8 on August 1 to 5,   
   then 5, 8, 6, 5 and 8 on August 6 to 10, 5 on August 11 to 21, then   
   8, 5, 12 and 10 on August 22 to 25, and 5 on August 26 to 31.   
      
   F. K. Janda, OK1HH predicts mostly quiet geomagnetic conditions   
   August 1, quiet to unsettled August 2 and 3, quiet to active August   
   4, quiet to unsettled August 5 and 6, quiet August 7, quiet to   
   active August 8, active to disturbed August 9, quiet to active   
   August 10 and 11, quiet August 12 to 15, mostly quiet August 16,   
   quiet August 17 and 18, mostly quiet August 19 and 20, quiet August   
   21, quiet to unsettled August 22, quiet to active August 23 and   
   active to disturbed on August 24.   
      
   Scott Bidstrup, TI3/W7RI commented, "You wrote: 'No sunspots? Sky   
   and Telescope recommends observing faculae.'   
      
   There's actually a good reason for hams to do so. Faculae actually   
   appear fairly bright in the 304 angstrom wavelength images of the   
   sun. When they are large and numerous, even in the absence of   
   significant sunspots, they can contribute significantly to the 304   
   angstrom ultraviolet that causes about half of our F2 ionization. So   
   when the sunspots are low, but the propagation isn't all that bad,   
   it's a good bet that there are a lot of faculae present on the solar   
   disk.   
      
   You can easily see if this is the case in the 304 angstrom image of   
   the sun, which can be found on my propagation web page at   
   http://www.bidstrup.com/w7ri-hf-radio-propagation.htm . The 304a   
   image is the upper right in the group of four solar images (the   
   image can be viewed full size by right-clicking the image and   
   selecting "view image" from the drop-down menu). Sunspots normally   
   appear as a bright, white spot in this image, but faculae appear as   
   bright orange areas surrounding the sunspots, much brighter than the   
   background granulation around them. The faculae may not be as bright   
   as the sunspots, but they make up for that in a much larger area on   
   the solar surface.   
      
   While the faculae don't show up quite as well in the 195 angstrom   
   image from the STEREO B spacecraft beacon, the green image just   
   below the 304a image on my page, it will give you an idea of what   
   faculae as well as active regions are about to rotate into view. So   
   it can be useful to watch these images to get an idea of what is   
   coming up - particularly for a contest weekend - it can help in   
   planning band strategies."   
      
   Thanks Scott!   
      
   Tomas Hood, NW7US, the propagation editor for CQ and several other   
   magazines, is publishing cool propagation and space weather   
   information throughout each day on his Space Weather and Radio   
   Propagation page on Facebook (see https://www.facebook.com/spacewx.hfradio ).   
      
   These posts include current images from the Solar Dynamics   
   Observatory (SDO) instruments that watch the Sun 24/7, daily space   
   weather and radio propagation conditions and forecasts, plus   
   educational tidbits that can enhance your understanding of this   
   exciting topic. Anyone who has a Facebook account can 'Like' and   
   have notifications turned on so that you can see alerts when these   
   page posts are made. Speaking of educational material, check out the   
   self-study course that Tomas is offering at http://nw7us.us/swc .   
      
   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 July 24 through 30 were 55, 65, 76, 110, 143,   
   160, and 145, with a mean of 107.7. 10.7 cm flux was 104, 107, 117,   
   121, 132, 142, and 152, with a mean of 125. Estimated planetary A   
   indices were 5, 6, 7, 5, 9, 4, and 5, with a mean of 5.9. Estimated   
   mid-latitude A indices were 6, 9, 9, 6, 12, 6, and 7, with a mean of   
   7.9.   
   NNNN   
   /EX   
      
      
   )\/(ark   
      
   One of the great tragedies of life is the murder of a beautiful theory by a   
   gang of brutal facts. --Benjamin Franklin   
      
   --- FMail/Win32 1.60   
    * Origin:  (1:3634/12.71)