SB PROP @ ARL $ARLP050   
   ARLP050 Propagation de K7RA   
      
   ZCZC AP50   
   QST de W1AW     
   Propagation Forecast Bulletin 50  ARLP050   
   >From Tad Cook, K7RA   
   Seattle, WA  December 12, 2014   
   To all radio amateurs    
      
   SB PROP ARL ARLP050   
   ARLP050 Propagation de K7RA   
      
   Compared to the previous seven days, solar activity dropped over the   
   past week December 4 to 10 with average daily sunspot numbers down   
   63.6 points to 88.4, and average daily solar flux off 32.5 points to   
   139.6. But both numbers were higher on December 11, a good sign.   
       
   The latest forecast has solar flux at 155, 160, and 165 on December   
   12 to 14, 170 on December 15 to 17, 165 on December 18, 170 on   
   December 19 and 20, 165 and 150 on December 21 and 22, 155 on   
   December 23 to 27, 150 on December 28 and 29, 145 and 140 on   
   December 30 and 31, 135 on January 1 to 4, then 140, 145, 150, 155   
   and 160 on January 5 to 9 and 165 on January 10 to 12. It then   
   reaches a peak of 175 on January 14 and 15.   
       
   Predicted planetary A index is 5 on December 12, 18 on December 13,   
   15 on December 14 and 15, 12 on December 16 to 18, 10 on December 19   
   and 20, 5 on December 21 to 27, 8 on December 28 to 30, 10 on   
   December 31 and January 1, then 12, 25, 15 and 10 on January 2 to 5,   
   8 on January 6 and 7, 10 on January 8 and 9, 8 on January 10 to 12,   
   10 and 12 on January 13 and 14, and 10 on January 15 and 16.   
       
   Let's see what OK1MGW has for us in his prediction for geomagnetic   
   conditions.   
       
   OK1MGW sees quiet to active conditions December 12 and 13, quiet to   
   unsettled December 14 and 15, quiet to active December 16 and 17,   
   quiet to unsettled December 18 to 20, mostly quiet December 21,   
   quiet December 22, mostly quiet December 23 and 24, quiet December   
   25 and 26, quiet to unsettled December 27 and 28, mostly quiet   
   December 29 to 31, quiet to unsettled January 1 and 2, active to   
   disturbed January 3, quiet to active January 4 and 5, and quiet to   
   unsettled January 6 and 7.   
       
   He believes there will be an increase in solar wind on December 13,   
   16 to 18 and January 2 to 5.   
       
   Don't forget this weekend is the annual ARRL 10 Meter Contest (see   
   http://www.arrl.org/10-meter for rules and general information).   
   This is a really fun event, and due to the nature of ten meters, it   
   always holds many surprises. The Geminids meteor shower peaks this   
   weekend, and it is likely that ionized meteor trails could enhance   
   propagation at the high end of the HF spectrum.   
       
   It is also really easy to get a ten meter station on the air with   
   minimal effort. A half-wave dipole is only about 16.5 feet long for   
   this band, and you can hang it off just about anything to get it   
   some minimal distance in the air. Also, Technician Class hams can   
   participate in this one using SSB on 28.3 to 28.5 MHz and CW on 28.0   
   to 28.3 MHz. There is also an easy 10 meter vertical described at   
   the ARRL URL above for the 10 meter contest.   
       
   I was predicting conditions should be slightly better than they were   
   during the 2013 contest, with somewhat higher solar activity about   
   the same geomagnetic instability. But now the geomagnetic conditions   
   look a little worse.   
       
   The December 10 planetary A index for December 12 to 14 was 5, 12   
   and 12. The December 11 forecast shows 5, 18 and 15 for those same   
   days, or a little bit worse. These daily forecasts are at   
   ftp://ftp.swpc.noaa.gov/pub/forecasts/45DF/ . Check it again today   
   after 2100 UTC. Maybe it will be better.   
       
   In 2013 the solar flux on Friday through Sunday on the contest   
   weekend was 141, 163 and 158, for an average of 154. This weekend   
   the predicted Friday through Sunday solar flux is 155, 160 and 165,   
   which averages out to 160. Last year the planetary A index over   
   those same three days was 3, 16 and 7, average value 8.7. This   
   year's forecast is 5, 18 and 15, with an average of 12.7.  We'll see   
   what happens.   
       
   Check 2013 bulletins at   
   http://www.arrl.org/w1aw-bulletins-archive/ARLP051/2013 and   
   http://www.arrl.org/w1aw-bulletins-archive/ARLP052/2013 to see a   
   comparison with propagation from previous years and what the numbers   
   were on the contest weekend.   
       
   NOAA Space Weather Prediction Center has transitioned to their new   
   servers, so you will want to check   
   ftp://ftp.swpc.noaa.gov/pub/indices/DSD.txt and   
   ftp://ftp.swpc.noaa.gov/pub/indices/DGD.txt for solar flux, sunspot   
   and geomagnetic indices, and   
   ftp://ftp.swpc.noaa.gov/pub/forecasts/45DF/ for the daily 45-day   
   forecast. Of course Canada still serves up their same three times   
   per day solar flux numbers from their observatory at both   
   http://www.spaceweather.ca/solarflux/sx-5-flux-eng.php and   
   ftp://ftp.geolab.nrcan.gc.ca/data/solar_flux/daily_flux_values/fluxtable.txt   
   Take your pick.  HTML or plain text.   
       
   Dick Bingham, W7WKR sent along some interesting historical material   
   on early amateur radio, assembled by W2PA. Check it out at   
   http://w2pa.net/HRH/ .   
       
   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 December 4 through 10 were 137, 97, 73, 58, 77,   
   80, and 97, with a mean of 88.4. 10.7 cm flux was 157.6, 136.8,   
   128.7, 131.8, 132.6, 139.7, and 149.8, with a mean of 139.6.   
   Estimated planetary A indices were 11, 11, 13, 28, 17, 15, and 9,   
   with a mean of 14.9.  Estimated mid-latitude A indices were 8, 8,   
   10, 19, 11, 12, and 6, with a mean of 10.6.   
   NNNN   
   /EX     
      
      
   )\/(ark   
      
   If you think it's expensive to hire a professional to do the job, wait until   
   you hire an amateur.   
      
   --- FMail/Win32 1.60   
    * Origin:  (1:3634/12.71)