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The K7RA Solar Update


No sunspots appeared last week. The previous seven days had only one big sunspot group on one day, with a sunspot number of 35. Over the seven-day period this averaged out to a sunspot number of 5, so average daily sunspot numbers declined from 5 to 0 this week.

Average daily solar flux also declined, by one point from 69.5 to 68.5.

Geomagnetic indicators were quiet, with average daily planetary A index declining from 5.1 to 4.1, and mid-latitude A index from 5 to 4.7. reports that the percentage of days with no sunspots so far in 2020 (76%) is close to 2019 (77%).

Every day I look at STEREO see if there are any hints of activity over the horizon. Each 30-degree division on that display represents about 55 hours, and currently on May 14 I see a bright possibly active area about 30 degrees over the solar horizon.

Predicted solar flux is 68 on May 15-21, 69 on May 22, 70 on May 23-31, 68 on June 1-13, 70 on June 14-27 and 68 on June 28.

Predicted planetary A index is 5 on May 15-18, 8 on May 19-20, 5 on May 21 to June 8, 8 on June 9-10, 5 on June 11-13, then 10 and 8 on June 14-15, and 5 on June 16-28.

Geomagnetic activity forecast for the period May 15 until June 9, 2020 from F.K. Janda, OK1HH.

Geomagnetic field will be

quiet on: May 26, June 2-5

quiet to unsettled on: May 16, 25, 27-31

quiet to active on: (May 15, 20-22, 24, June 1, 6-8)

unsettled to active on: (May 17-19, 23)

active to disturbed: no disturbances predicted

Solar wind will intensify on: May (18-21, 23,) 24, June (6-7)

– Parenthesis means lower probability of activity enhancement.

– The predictability of changes remains lower as there are no indicators.

I’ve recently noticed that even with very little sunspot activity, there is plenty of activity on the air. Checking FT8 communications on I can see lots of weak signal communication over marginal paths, even on 12, 10, and 6 meters. I also get reports from readers, and see reports on a local DXer email list, and everyone seems more active of late.

I suspect much of this activity is related to the COVID-19 pandemic, and the great number of operators isolating at home.

The May 7 ARRL Eclectic Tech podcast (listen at features a story (starting at minute 10:57) about a medical research project using distributed computing employing idle microprocessor cycles in volunteer’s personal computers to aid in medical research. Called Folding at Home ( participants can form teams to do the work, and keep score. It has recently been re-positioned to aid research on COVID-19.

Twenty years ago, I started a folding team, dedicated to the memory of the former holder of my call sign, K7RA. You can view the stats on our team at If you can join us, download the software from and during installation please dedicate your work to team number 10566.

I was aware of the Carrington Event (see, the huge solar storm of 1859, but there was another big one, 99 years ago this week, that also set fire to telegraph offices and caused general mayhem. See and

Ken Brown, N4SO, (EM50) in Grand Bay, Alabama reports unusual 15-meter propagation at an odd time, after midnight where he is. On May 11, using FT8 he heard VE7SKY (CN89) at 0602 UTC and then 8C2WFH, (OI53) in Indonesia at 0649 UTC.

Mark Bell, K3MSB, of Airville, Pennsylvania wrote on May 8: “Ten meters has been open the past few days. I’ve worked stations in Texas and California on Thursday May 7, and stations in Minnesota and Washington on May 8, using CW and 100 watts. It was classic Es propagation. I had no RBN reports for the 7th, but nice ones on the 8th. Several other stations were calling me on the 8th, but I was unable to work them.”

On May 11 Mark wrote: “Here’s an update to my update. Between May 7-10, I worked 10 states on 10-meter CW. Single hop sporadic-E into Texas, Minnesota, Florida, Tennessee, Missouri, Louisiana, and Wisconsin, and double hop into California, Washington, and Idaho – all on CW. I heard quite a few more stations calling me, but I was unable to work them.”

Marked mentioned RBN – the Reverse Beacon Network. To learn more, see

Jon Jones, N0JK, wrote from Kansas: “Es on May 11. Caught J68HZ (St. Lucia) on 50.313 MHz at 2345z on double-hop Es. My report was -24 dB! So far, no major openings like on April 15, but the Es season is starting to pick up.”

Danny Miller, KB8W, wrote: “There was a nice Es opening on 6 meters during the afternoon and evening of May 8 from my Upper Peninsula home (EN57) to Idaho, western Montana, Alberta and Saskatchewan. Es is common in the central US during the summer months, but it is early to have it happen so far north. The Es cloud appeared to be over North and South Dakota.

“I worked 12 stations over about ten hours, using FT8 on 50.313 MHz. I run only 50 W to a 5 element Yagi on 6 meters, so it is great to have some extended propagation to help me work those western grid squares!”

K0ZN wrote from De Soto, Kansas: “May 7 had some exceptional HF conditions. I have not heard things this good in several years. What got my attention was when I turned the radio on at about 11 PM, WWV was pounding in at 35 dB over S-9 on 10 and 15 MHz and S-9 on 20 and S-7 on 25 MHz here in Kansas City; that is only a 550 mile path, quite short for 20 and 25 MHz at that time. I got on 10 meters and heard strong west coast signals and worked a Hawaiian running 30 W to a vertical with good signals both ways. The impressive thing was hearing a Russian who was S-9 working a Polish station! Thirty meters was clearly wide open to a large part of the world….at midnight CST. One can only hope this is an omen of better things coming on HF.”

If you would like to make a comment or have a tip for our readers, email the author at

For more information concerning radio propagation, see and the ARRL Technical Information Service at For an explanation of numbers used in this bulletin, see

An archive of past propagation bulletins is at More good information and tutorials on propagation are at

Monthly propagation charts between four USA regions and twelve overseas locations are at

Instructions for starting or ending email distribution of ARRL bulletins are at

Sunspot numbers for May 7 through 13, 2020 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 0. 10.7 cm flux was 68.7, 67.9, 71, 67.9, 66.2, 68.9, and 68.8, with a mean of 68.5. Estimated planetary A indices were 4, 4, 3, 5, 5, 4, and 4, with a mean of 4.1. Middle latitude A index was 5, 4, 3, 5, 7, 5, and 4, with a mean of 4.7. (

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