SB PROP @ ARL $ARLP015   
   ARLP015 Propagation de K7RA   
      
   ZCZC AP15   
   QST de W1AW   
   Propagation Forecast Bulletin 15  ARLP015   
   > From Tad Cook, K7RA   
   Seattle, WA  April 11, 2014   
   To all radio amateurs   
      
   SB PROP ARL ARLP015   
   ARLP015 Propagation de K7RA   
      
   Average daily solar flux weakened over the past seven days, and so   
   did the outlook for the near term, at least until Thursday, April   
   10. Average daily solar flux declined from 149 to 142.2, while   
   average daily sunspot numbers remained about the same, moving from   
   130.4 to 129.3   
      
   > From the NOAA/USAF 45 day forecast, predicted solar flux is 140 on   
   April 11-12, 145 on April 13-15, 150 on April 16-18, 140 on April   
   19, 135 on April 20-23, 130 on April 24-27, 125 on April 28 through   
   May 3, and 140 on May 4-6.   
      
   In yesterday's ARRL Letter we reported the prediction from   
   Wednesday, April 9 showed an average daily solar flux of 133.3 over   
   April 10-15. But just two days earlier, on Monday April 7 the   
   predicted average for the same period was 142.5, and back on March   
   30 the prediction for April 10-15 showed an average solar flux of   
   145.8. The predicted solar flux for April 10 was 150 on March 30,   
   140 on April 7 and 130 on April 9, which indicated a progressively   
   pessimistic outlook.   
      
   However, the April 10 prediction showed higher values. For April   
   11-18, average solar flux is predicted at 145.6, ten points higher   
   than the prediction for the same eight days on April 9, which was   
   135.6.   
      
   Predicted planetary A index is 5 on April 11, 8 on April 12, then 12   
   on April 13, 8 on April 14-15, 5 on April 16-18, 8 on April 19, then   
   5 on April 20 through May 5, and 8 on May 6-7.   
      
   OK1HH predicts a quiet geomagnetic field on April 11-13, mostly   
   quiet April 14, quiet to unsettled April 15-16, quiet to active   
   April 17, quiet April 18, mostly quiet April 19-20, quiet to active   
   April 21, quiet to unsettled April 22, mostly quiet April 23, quiet   
   on April 24, mostly quiet April 25-26, quiet April 27, mostly quiet   
   April 28, quiet on April 29, mostly quiet April 30, quiet May 1-2,   
   mostly quiet May 3, quiet to unsettled May 4, quiet May 5, quiet to   
   unsettled May 6, and back to quiet again on May 7-8.   
      
   A week ago (but too late for this bulletin) NASA released their   
   monthly Solar Cycle prediction, little changed from the March   
   version:   
      
   http://solarscience.msfc.nasa.gov/predict.shtml   
      
   The forecast begins, "The current prediction for Sunspot Cycle 24   
   gives a smoothed sunspot number maximum of about 70 in the late   
   summer of 2013. The smoothed sunspot number reached 73.1 in   
   September 2013, so the official maximum will be at least this high."   
      
   The March forecast said "The current prediction for Sunspot Cycle 24   
   gives a smoothed sunspot number maximum of about 69 in the late   
   summer of 2013. The smoothed sunspot number reached 68.9 in August   
   2013, so the official maximum will be at least this high."   
      
   These are smoothed numbers, averaged over a year, so that is why the   
   numbers from the end of last summer changed, because recent higher   
   activity is now averaged in.   
      
   Here is an interesting article, "Small Groups, Big Flares" from   
   Belgium's Solar Influences Data Center:   
      
   http://sidc.oma.be/news/245/welcome.html   
      
   Wayne Starnes, KU4V of Cary, North Carolina sent an email concerning   
   the radio blackout mentioned in last week's bulletin:   
      
   "Yes I also experienced the blackout during the CQ WPX, but do not   
   actually recall the time it happened. I was running on 10M as I   
   recall and BOOM 20+ atmospheric noise on the band! I then checked   
   10m-160m and it was the same intensity on every band. I have never   
   heard anything like it.   
      
   "Then, after a few minutes, it stopped and the bands seemed to be in   
   better shape actually.   
      
   "Then, Sunday 30-Mar at 1503 UTC while running 10m, YB2DX calls me,   
   very weak but we made it. At 1522 UTC YC0IEM calls me, again very   
   weak but we made it. At 1547 UTC 4Z5ML called.   
      
   "After the contest, 31-Mar after 0200 I worked the TX5 guys on 10   
   and 15.   
      
   "Amazing and interesting propagation this past weekend."   
      
   Chris Wreck, K2HVE of Bayonne, New Jersey wrote: "Yes! It was the   
   same at my station, K2HVE. I am located in Hudson County, 1.5 miles   
   SW of the Statue of Liberty and 2.5 miles SW of WTC in lower   
   Manhattan. I was on 20 meters during the CQ WPX Contest on Saturday   
   29 March working EU and Russian stations one after another when   
   around 1750 UTC the whole band was wiped out. Nothing but noise at   
   an S3 level. It was like somebody pulled my antenna wire out. I   
   began checking antenna connections on my IC-7600 and found nothing.   
      
   "Very shortly a NOAA SWPC alert came through noting the solar flare.   
   The disturbance lasted about 30-45 minutes, then slowly the US   
   Stations came back up and shortly after the EU Stations. In an hour   
   it was like nothing had ever happened. In all the years I never had   
   anything so sudden happen at my QTH regarding Ole' Sol."   
      
   Jon Jones, N0JK sent a correction concerning working long path on   
   6-meters.   
      
   "Fred, KH7Y made the first 6 meter Hawaii to Europe TPL (trans-polar   
   longpath) contact of solar cycle 24 with IT9 on February 28. But it   
   was TPL going southeast of Hawaii. It took place in the early   
   afternoon HST (Hawaii Standard Time).   
      
   "I think I made the first Hawaii to Europe TPL contact of Solar   
   Cycle 24 going southwest of Hawaii March 30 with S57RR. It was   
   around midnight HST for me."   
      
   Jon also reported, on April 10: "During the last week many contacts   
   were made in the afternoon from the Gulf Coast and southern parts of   
   the Midwest to CX, LU and PY in South America on 6 meters. A few   
   fortunate hams in AR, MO and OK worked the Falkland Islands. The   
   propagation mode is 'afternoon TEP.' This link has information about   
   this propagation mode:   
      
   "http://home.iprimus.com.au/toddemslie/aTEP-Harrison.htm   
      
   "Not much to report since arriving home (to Kansas) from Hawaii. I   
   heard CE4WJK working CO2QU on April 6 at 2100 UTC on 50.140 MHz.   
      
   "Today April 10 heard the K5AB/b 50.060 MHz on Es at 2350 UTC."   
      
   Thanks, Jon!   
      
   Scott Craig's Solar Data Plot Utility has an updated data file,   
   useful if you are just starting out with the program. Otherwise you   
   update it auto-magically weekly with this bulletin.   
      
   You can find it at http://www.craigcentral.com/sol.asp .   
      
   This program runs on Microsoft Windows, but I've never been able to   
   use it on Windows 7 computers, so I've used a virtual XP mode or   
   just my old XP machine. Now I see Microsoft has ended support for   
   XP.   
      
   This weekend is the Japan International DX CW Contest. See details   
   at http://jidx.org/ .   
      
   If you would like to make a comment or have a tip for our readers,   
   email the author at, k7ra@arrl.net.   
      
   For more information concerning radio propagation, see the ARRL   
   Technical Information Service web page 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 April 3 through 9 were 137, 174, 172, 127, 106,   
   94, and 95, with a mean of 129.3. 10.7 cm flux was 153, 156.9,   
   142.1, 140.9, 139.9, 132, and 130.6, with a mean of 142.2. Estimated   
   planetary A indices were 6, 6, 14, 5, 11, 5, and 5, with a mean of   
   7.4. Estimated mid-latitude A indices were 7, 5, 11, 3, 10, 4, and   
   5, with a mean of 6.4.   
   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)