TZUTC: -0500   
   MSGID: 486.fidonet-ls_arrl@1:2320/33 28df911a   
   PID: Synchronet 3.20a-Win32 master/1c63f4d2c May 24 2023 MSC 1929   
   TID: SBBSecho 3.20-Win32 master/1c63f4d2c May 24 2023 MSC 1929   
   BBSID: TBOLT   
   CHRS: ASCII 1   
      
   SB PROP @ ARL $ARLP022   
   ARLP022 Propagation de K7RA   
      
   ZCZC AP22   
   QST de W1AW    
   Propagation Forecast Bulletin 22  ARLP022   
   From Tad Cook, K7RA   
   Seattle, WA  June 2, 2023   
   To all radio amateurs   
      
   SB PROP ARL ARLP022   
   ARLP022 Propagation de K7RA   
      
   Average daily solar flux values dropped over the past week, but   
   sunspot numbers were nearly the same, comparing May 25 to 31 to the   
   previous week.   
      
   Average daily solar flux declined from 161.2 to 155.3. Geomagnetic   
   indicators were quieter, with average daily planetary A index   
   declining from 17.1 to 7.3, and middle latitude numbers from 14.4 to   
   7.9.   
      
   Predicted solar flux is 160 on June 2, 155 on June 3-4, 150 on June   
   5-8, 130 on June 9-11, then 135, 140, 143, 145, and 150 on June   
   12-16, 155 on June 17-20, 150 on June 21-25, then 145, 140 and 135   
   on June 26-28 and 130 on June 29 to July 8.   
      
   Predicted planetary A index is 15, 12, 10 and 8 on June 2-5, 5 on   
   June 6-17, then 22, 15, 12 and 10 on June 18-21, 5 on June 22-24, 12   
   and 10 on June 25-26, then 5 on June 27-28, then 15, 12, 15, 10 and   
   8 on June 29 through July 3, then 5 on July 4 through the middle of   
   the month.   
      
   Weekly Commentary on the Sun, the Magnetosphere, and the Earth's   
   Ionosphere - June 1, 2023 from OK1HH.   
      
   "The Sun still surprises us, it has been in the habit for billions   
   of years, but we only observe it for a few hundred years. So, we   
   have a right to be surprised by what it is doing and what we can   
   observe with instruments on satellites and powerful solar telescopes   
   on Earth, including the largest four-metre one on the island of Maui   
   in Hawaii, which can see the very fine structures of sunspot nuclei.   
      
   "What's more, we're seeing spots on the far side of the Sun that are   
   so big, they affect the vibration of the whole Sun. But we can only   
   see their structure and predict possible flares after they appear on   
   the eastern limb of the solar disk, which was not at all the case   
   with the current most active AR3315, which did not appear there. It   
   emerged later, thereafter began to grow rapidly.   
      
   "Conversely, the source of the next big flare was hidden behind the   
   southeastern limb, and we only saw the prominence above it.   
      
   "Meanwhile, the larger groups of sunspots have mostly moved to the   
   western half of the solar disk. A large coronal hole in the southern   
   hemisphere now crosses the central meridian. This increases the   
   likelihood of geomagnetic disturbances starting on June 2."   
      
   Mike, AK7ML wrote:   
      
   "I recall in a movie about Pearl Harbor that they could not reach   
   Hawaii from stateside on HF and then they sent the message by cable   
   telegraph in routine status, so Pearl was not informed of the attack   
   in time.   
      
   "For years I have been able to work Australia in the morning and now   
   it is Indonesia that is workable instead!"   
      
   A story about a big sunspot:   
      
   https://www.fox9.com/news/giant-sunspot-ar3310-visible-earth   
      
   I've added information from this resource to the text appearing at   
   the bottom of every propagation forecast bulletin (this resource   
   comes from September 2002 QST):   
      
   https://www.arrl.org/files/file/Technology/tis/info/pdf/0209038.pdf   
      
   I was sad to learn that old friend Chip Margelli, K7JA became a   
   Silent Key on May 25. Chip was from the Seattle area, and first came   
   to my attention when he became proficient in the Japanese language   
   during high school, then specialized in running JA stations at the   
   old Rush Drake, W7RM contest station on Foulweather Bluff in Puget   
   Sound.  At one time he may have been the most famous American ham in   
   Japan, or so I heard at the time.   
      
   Send your tips, reports, observations, questions, and comments to   
   k7ra@arrl.net. When reporting observations, don't forget to tell us   
   which mode you were operating.   
      
   For more information concerning shortwave radio propagation, see   
   http://www.arrl.org/propagation and the ARRL Technical Information   
   Service at http://arrl.org/propagation-of-rf-signals . For an   
   explanation of 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/ .   
      
   Instructions for starting or ending email distribution of ARRL   
   bulletins are at http://arrl.org/bulletins .   
      
   Sunspot numbers for May 25 through 31, 2023 were 121, 127, 125, 119,   
   153, 144, and 147, with a mean of 133.7. 10.7 cm flux was 152.1,   
   149, 156.9, 151.3, 154.4, 162, and 161.4, with a mean of 155.3.   
   Estimated planetary A indices were 11, 6, 4, 11, 4, 5, and 10, with   
   a mean of 7.3. Middle latitude A index was 11, 6, 5, 11, 5, 6, and   
   11, with a mean of 7.9.   
   NNNN   
   /EX   
   --- SBBSecho 3.20-Win32   
    * Origin: The Thunderbolt BBS - Little Rock, Arkansas (1:2320/33)   
   SEEN-BY: 1/120 123 15/0 18/0 50/109 90/1 105/81 106/201 116/17 18   
   SEEN-BY: 116/116 123/0 10 25 131 170 180 200 525 755 3001 135/115   
   SEEN-BY: 135/300 153/7715 154/10 30 40 50 700 218/700 840 220/70 90   
   SEEN-BY: 221/1 6 222/2 226/17 18 30 227/114 229/110 112 113 206 307   
   SEEN-BY: 229/317 426 428 470 664 700 240/1120 1200 250/1 266/512 267/800   
   SEEN-BY: 275/1000 282/1038 291/111 299/6 301/1 113 317/3 320/219 322/757   
   SEEN-BY: 335/364 341/66 342/200 396/45 460/58 467/888 633/267 280   
   SEEN-BY: 633/281 412 418 712/620 848 1321 770/1 100 340 772/210 220   
   SEEN-BY: 772/230 2320/0 33 105 304 401 3634/0 12 27 56 57 119 5001/100   
   SEEN-BY: 5005/49 5020/715 1042 4441 5030/49 5058/104 5061/133 5064/56   
   SEEN-BY: 5075/128 5083/1 444 5090/958   
   PATH: 2320/33 105 154/10 3634/12 5020/1042 301/1 221/6 218/840   
   PATH: 770/1 712/848 633/280 229/426