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The K7RA Solar Update


The past reporting week (October 12-18) saw very little solar activity, with a sunspot number of 12 on October 15, meaning the average daily sunspot number was only 1.7, down from the already low average of 8.4 over the previous seven days.

Over the same two periods, average daily solar flux declined from 76.8 to 70.5, while average daily planetary A index increased from 8.9 to 21.1 and average mid-latitude A index went from 8 to 16.7.

Dr. Skov says there are sunspots just beyond the solar horizon which should soon come into view and begin to affect Earth:

Predicted solar flux over the near term is 74, 78 and 82 on October 20-22, 86 on October 23-26, 72 on October 27 through November 2, 70 on November 3-14, 72 on November 15-29, then 70 on November 30 through December 3.

Predicted planetary A index is 8 on October 20-21, then 10, 5, 35 and 45 on October 22-25, 15 on October 26-27, then 10, 8, 5 and 5 on October 28-31, then 8 and 10 on November 1-2, 5 on November 3-6, then 28, 30, 40, 28, 26, 18 and 10 on November 7-13, then 12 on November 14-15, 8 on November 16-18, then 5, 35 and 45 on November 19-21, 15 on November 22-23, then 10 and 8 on November 24-25, 5 on November 26-27, then 8 and 10 on November 28-29, and 5 on November 30 through December 3.

Geomagnetic activity forecast for the period October 20 to November 15, 2017 from F.K. Janda, OK1HH.

“Geomagnetic field will be:
Quiet on October 20, 30-31, November (19)
Quiet to unsettled on October 22, 28-29, November 1-6, 13-15
Quiet to active on October 21, 23-27, November 7, 9-12
Active to disturbed on November 8

Amplifications of the solar wind, mostly from coronal holes, are expected on October (22, 24,) 25-26, November 7-12

- Amplifications of the solar wind-prediction is less reliable at present.
- Parenthesis means lower probability of activity enhancement and/or lower reliability of prediction.”

Jeff, N8II of Shepherdstown, West Virginia sent this report on October 13: “Punk conditions with the K index as high as 6 and almost always at least 4 during the last 3 days, but I heard VU7T Lakshadweep Island around 20Z with S5-7 signals and worked Spain and Gibraltar on 15-meter CW in the morning on October 12. Today many Europeans were readable calling 3C0L, Annobon Island, on 20-meter CW and I finally did work them.”

On October 19, Jeff added: "Surprisingly, with the SFI running 69-72 recently, 15 meters has been open to at least southern Europe for the past 4 days. I have also worked Reunion Island, FR4QK, on October 11 and heard 9J2BO in Zambia on 15-meter CW. Two ops from Lithuania have been doing an outstanding job of decreasing worldwide demand for Annobon Island off the west coast of Africa while operating there as 3C0L.

“They had a good signal on all bands 160 through 12 meters here and I have made QSOs with them on all HF bands except 40, 30, and 10 meters. They were very good copy on 160 meters throughout the evening on October 16 and 18. They were S9+20-25 dB on 15-meter SSB on October 18 at around 2100Z and easily working to the West Coast. Conditions on 15 have also been good to the Middle East around 1300-1500Z most days and I’ve contacted Israel, Lebanon, Saudi Arabia, United Arab Emirates, and Qatar."

K2CHM from Framingham, Massachusetts reported on October 13: "Much to my surprise and pleasure I worked ZD7FT on St Helena Island SSB at 1950 UTC October 11 on 28.489 MHz.  My location is FN42 in eastern Massachusetts and I am only running 60 W to a dipole about 20 feet off the ground."

David Moore sent this link:

Jon Jones, N0JK in Kansas sent these notes on October 16: “Sporadic-E is rare in October, the only month of the year with less is March. Any Es in October is a Halloween treat!

“There has been sporadic-E on 6 Friday 10/13, Saturday 10/14 and Sunday 10/15 this weekend. Perhaps associated with the high geomagnetic activity. Sunday was probably the best.

“From work, I logged KM4SEG EL88 at 1648z on October 15 on SSB at 50.145 MHz. I was using the old MFJ-9406 with 10 W output to a 1/4 wavelength magnetic-mount whip. It was a solid contact and I received 5x5 to 5x7 reports. I heard, but didn't work, AE2DX. I noticed that Florida stations had Es openings to Texas from 1500z to after 1900z.

“Most activity was initially old school CW and SSB. Later, there were some FT8 signals.

“That afternoon the Es - TEP link path opened from New England to Chile and Argentina.

“LU5FF        2206Z 50105.2 FF99 FN42 599                   NK1K    
“LU5FF        2206Z 50105.2 FF99<>FN42 599                  NK1K    
“LU5FF        2202Z 50105.0 s5 FN44 MAINE                   K1TOL 

“Both CW and FT8 QSOs were logged. Great to see some F-layer DX this late in the solar cycle.

“More 6 meter sporadic-E on October 16.

“KD4ESV in Florida spotted the HI8W/b and some domestic station spots:

“KD4ESV       1811Z  50125.0 EM57<ES>EL87RL                  WA4Q    
“K8TV         1809Z  50125.0 EN81 EL87 58 52                 KD4ESV  
“W3DOG/b        1802Z  50071.0 469 QSB IN (LOWER ALABAMA)   WB4JPG  
“W4IMD        1759Z  50125.0                                 K1TTT   
“N9RD         1757Z  50125.0 EN61 EL87 57                    KD4ESV   

“More 50 MHz activity: Some weak Es on October 16 allowed links to TEP. I heard LU5FF on 50.105 MHz CW and had audible tones on CE2AWW at. CE2AWW worked stations from W1, W2, W4, W5 west to California. K5CM in em25 had CE2AWW s9+ at 2352z. Both LU5FF and CE2AWW operated CW and FT8.”

Another piece on Hisako Koyama:

There is an Athens Astronomical Association in Athens, Georgia and Athens Astronomical Society in Athens, Ohio, but I believe this is the Ohio organization: Looks like a useful event of interest to sun watchers.

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Sunspot numbers for October 12 through 18, 2017 were 0, 0, 0, 12, 0, 0, and 0, with a mean of 8.4. 10.7 cm flux was 70.2, 69.7, 69, 70.3, 70.9, 70.3, and 73.2, with a mean of 76.8. Estimated planetary A indices were 29, 42, 31, 26, 9, 6, and 5, with a mean of 8.9. Estimated mid-latitude A indices were 20, 26, 26, 31, 6, 4, and 4, with a mean of 8.