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The K7RA Solar Update

07/05/2019

Tad Cook, K7RA, in Seattle, reports: Solar activity remains very low. Over the past 2 weeks, only 4 days had visible sunspots, so the average daily sunspot number went from 6.7 in last week’s report to 1.6 this week.

Average daily solar flux remained the same, moving only from 67.4 to 67.5. Geomagnetic activity was also flat, with average daily planetary A index changing from 5 to 4.9, and average daily mid-latitude A index from 5.7 to 5.1.

Predicted solar flux over the next 45 days is also flat, with solar flux at 68 on July 5 – 12; 67 on July 13 – 19; 68 on July 20 – August 3; 69 on August 4 – 5; 68 on August 6 – 7; 67 on August 8 – 15, and 68 on August 16 – 18.

Predicted planetary A index is 18 and 10 on July 5 – 6; 5 on July 7 – 8; 10, 15, 12, and 8 on July 9 – 12; 5 on July 13 – August 1; 8 on August 2; 5 on August 3 – 5; 8 on August 6 – 7, and 5 on August 8 – 18.

F.K. Janda, OK1HH, sent this geomagnetic activity forecast for the rest of July. Geomagnetic field will be: 

  • Quiet on July 12 – 16, 25 – 26
  • Quiet to unsettled on July 8 – 9, 17, 20 – 21, (27)
  • Quiet to active on July 10 – 11, (19, 21, 24)
  • Unsettled to active on July 6 – 7, (18, 22-23, 28 – 31)
  • Active to disturbed on July 5
  • Solar wind will intensify on July 5 – 7, (8 – 9,) 10 – 11, (17 – 19, 22 – 24)

(Parentheses mean lower probability of activity enhancement.) 

Next geomagnetic activity forecast will be issued on July 18. 

Thanks to N7SO for this article from Sky & Telescope magazine. 

Spaceweather.com reported this week that a sunspot from new (i.e., next) solar Cycle 25 appeared briefly on July 1. This is based on the fact that the polarity of the sunspot, which was visible so briefly that it was not assigned a number, was opposite that of spots from current Cycle 24. 

So far Cycle 25 sunspots have appeared on December 20, 2016; April 8 and November 17, 2017, and May 28 and July 1, 2018.

Sunspot numbers for June 27 through July 3, 2019 were 11, 0, 0, 0, 0, 0, and 0, with a mean of 1.6. The 10.7-centimeter flux was 67, 68.1, 67.6, 67.4, 68.2, 67.3, and 66.9, with a mean of 67.5. Estimated planetary A indices were 4, 4, 3, 4, 9, 5, and 5, with a mean of 4.9. Middle latitude A index was 4, 5, 3, 3, 10, 5, and 6, with a mean of 5.1.

Back in April, some new solar cycle predictions were published. Note there is no expectation for another Maunder Minimum.

On July 1, K1HTV made what may be the first documented transatlantic 50 MHz two-way contacts using the new FT4 mode. The first FT4 contact at 1854 UTC was completed with F5SSD and 5 minutes later, with IZ8WGU.

Wayne, W2ZDP, in Clinton, North Carolina, reports:

“On July 1, starting about 1400Z, when I first noticed it at my location in FM04, 6 meter FT8 was like 20 meter FT8, with Europe coming in all day long, lasting until about 2000.

“I’m sure that I’m not the only one to comment on this, but I only have a modest 6 meter station — 100 W to a 4-element beam at 30 feet. I have never witnessed such a prolific opening to Europe since I moved from FN02 to FM04.

“When was all said and done, I managed to work 14 countries and 22 grids. This would have been a normal day on 17 meters, but on 6...spectacular!”

For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out K9LA’s Propagation Page.

A propagation bulletin archive is available. Monthly charts offer propagation projections between the US and a dozen DX locations.

Share your reports and observations. 



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