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The K7RA Solar Update


At 2347 UTC on November 17 the Australian Space Forecast Centre issued a Geomagnetic Disturbance Warning.

“Geomagnetic conditions are expected to rise from quiet to minor storm levels on 18 November due to the expected effect of a high speed solar wind stream from a coronal hole and possible glancing blow from the CMEs observed late on 15 and early on 16 November. This coronal hole effect may keep the conditions enhanced to unsettled to minor storm levels on 19 November.”

Increased geomagnetic activity expected due to coronal hole high speed wind stream from 18-19 November, 2015”

Solar activity declined again this week, with average daily sunspot numbers for the November 12-18 reporting week at 43.3, down from 72.3 during the previous seven days. Average daily solar flux was 105.5, down from 109.4.

Geomagnetic A indices were down, which is generally a good thing for HF propagation. The average daily planetary A index slipped from 25 to 11 and average daily mid0-latitude A index from 19 to 9. All four of these average A indexes being whole integers is an odd occurrence.

Predicted solar flux is 108 on November 20-21, 110 on November 22-23, 108 on November 24, 100 on November 25-26, 110 on November 27, 115 on November 28-29, 120 on November 30 and December 1, 115 on December 2, 110 on December 3-4, and 105 on December 5-14. Flux values then drop to a low of 95 on December 17-18, then rise back to 120 on December 27-28.

Predicted planetary A index is 10 on November 20, 8 on November 21-24, then 15, 10 and 5 on November 25-27, 8 on November 28-29, 25 on November 30 and December 1, then 15, 8, 5, 12, 20 and 25 on December 2-7 and 18, 8, 12, 10, 8, 10 and 8 on December 8-14. Another period of high geomagnetic activity is December 27-28, when a planetary A index of 25 is forecast.

The planetary A index is a metric related to geomagnetic conditions, and OK1HH of the Czech Propagation Interest Group has his own geomagnetic forecast, related here.

He expects the geomagnetic field will be mostly quiet November 20, quiet on November 21-25, quiet to unsettled November 26, quiet conditions again no November 27-28, quiet to unsettled November 29, active to disturbed November 30 through December 3, quiet to active December 4-6, active to disturbed December 7-8, quiet on December 9, quiet to unsettled December 10, mostly quiet December 11, quiet to unsettled December 12-13, quiet December 14 and quiet to active December 15.

OK1HH also predicts increased solar wind on November 20-22, 29-30, December 1-2, 5-12, and 16-20. Now here it gets a bit complicated. He sees a lower probability of enhanced solar wind on November 20-22, December 1, 5-7, 11-12 and 16-20. Got that?

These numbers look pretty good for the ARRL Phone Sweepstakes this weekend. ARRL Sweepstakes is a great domestic contest with a long history, and if you want to have some fun with a casual effort, getting on as a new participant in the last few hours of the contest is always a good idea.

There will be hundreds of weary operators trying to squeeze out a few more contacts, and you will be a fresh new one who they will all want to work.

Because ARRL Sections constitute multipliers, your desirability will be enhanced if you are in a rare or obscure location. The Canadian province of Ontario is divided into four sections, each one a multiplier, is often a desired contact.

In recent years (it changes from year to year) some of most sought after ARRL Sections were Newfoundland, Labrador, Virgin Islands, Puerto Rico, South Florida, North Dakota, Northern New York, Ontario North, Northern Territories, and Manitoba.

See for rules and details. Note you can only operate 24 hours out of the 30 hour contest period.

In a message about current 10 meter propagation, Carl Zellich, AA4MI, wrote, “It’s been a long time since 10 meters really opened up. On Friday, Nov 14, (did he mean Saturday?) it really rocked.

“From 10:30 EST (1530 UTC) it was opened to both Eastern and Western Europe with a few from North Africa until 11:00 EST (1600 UTC). Then it closed.

“But during that 30 minutes (after all these solar ejections let up), I worked 25 stations on CW at 30 wpm with very little QSB! Maybe the arrival of the Fall season had something to do with it too.”

David Moore sent this article about magnetic loops on the sun revealed in ultraviolet light:

This message came from Jeff Hartley, N8II, in Shepherdstown, West Virginia last week:

“Even when the K index dropped to 1 after the major storm this week, it seemed that 10 meters was relatively poor.

“Today (November 13) from 1440 UTC until around 1530 UTC, I had a pipeline into the Netherlands and Belgium. The first few 10 meter SSB QSOs were good signals from England, then there was a parade of PA, PD, and ON stations many peaking over S-9 with 25-100 W and very simple random wires and even one with an indoor dipole.

“The last few QSOs were with Germany with good signals and mostly non-gain antennas. The K index had climbed to 3 at 1500 UTC after a 1 at 0900 UTC.

“It seems to me that quite often even some northerly paths are not closed when the K index is 3 and may even be temporarily enhanced a bit. But overall, a K of 0 or 1 is best.

“CW Sweepstakes last weekend was enhanced somewhat in the lower 48 on 20 meters in particular. I made over 420 20 meter QSO's using my 80 meter dipole fed with ladder line including many on backscatter who were good copy. The North territories (missed here) and Alaska were much weaker than normal and at times especially Saturday evening western Canada seemed surprised despite loud signals (QRM) from Minnesota.”

Thanks, Jeff.  Great report!

Julio Medina, NP3CW, (FK68xk) in San Juan, Puerto Rico sent a list of stations he heard and worked on 6 meters:

“Today November 13 I heard PP1CZ/B on 50.085 MHz, 549 at 2253 UTC. CX1AA/B 50.083 MHz, 339-549 at 2255 UTC.

“Worked LU1WI on 50.090, 559 at 2318 UTC  FE77
“LU8EHR on 50.090, 559 at 2320 UTC
“LU1YT on 50.090, 559 at 2324 UTC in FE49”

Jon Jones, N0JK, from Kansas wrote on November 13: “There was a long lasting and strong sporadic E opening on 50 MHz the morning of November 11. Stations from W8 worked west to Colorado, Kansas and Nebraska stations worked east to W4 and W8 and west to Arizona and New Mexico. I worked W7DXW DM42mg (Tucson, Arizona) near the end of the opening at 1749z from EM28 on 50.125 MHz.”

For more information concerning radio propagation, see the ARRL Technical Information Service at For an explanation of the numbers used in this bulletin, see An archive of past propagation bulletins is at More good information and tutorials on propagation are at

My own archives of the NOAA/USAF daily 45 day forecast for solar flux and planetary A index are in downloadable spreadsheet format at and .

Click on “Download this file” to download the archive, and ignore the security warning about file format. Pop-up blockers may suppress the download.

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 November 12 through 18 were 29, 50, 48, 63, 44, 33, and 36, with a mean of 43.3. 10.7 cm flux was 103.5, 102.9, 106.3, 105.8, 105.6, 107.1, and 107.6, with a mean of 105.5. Estimated planetary A indices were 5, 14, 10, 9, 14, 8, and 17, with a mean of 11. Estimated mid-latitude A indices were 4, 12, 10, 7, 9, 7, and 14, with a mean of 9.




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