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ARRL Propagation Bulletin ARLP047 (2015)

ARLP047 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 47  ARLP047
From Tad Cook, K7RA
Seattle, WA  November 20, 2015
To all radio amateurs 

ARLP047 Propagation de K7RA

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 mid-latitude A index from 19 to 9. All four
of these average A indexes being whole integers is an odd

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 L O N G 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

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 QSOs 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."

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 the ARRL
Technical Information Service web page 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.