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ARRL Propagation Bulletin ARLP047 (2019)

SB PROP @ ARL $ARLP047
ARLP047 Propagation de K7RA

ZCZC AP47
QST de W1AW  
Propagation Forecast Bulletin 47  ARLP047
From Tad Cook, K7RA
Seattle, WA  November 22, 2019
To all radio amateurs 

SB PROP ARL ARLP047
ARLP047 Propagation de K7RA

We have not seen any sunspots since November 2, and at that time
they were only visible for two days, and prior to that no sunspots
since October 2.

According to Spaceweather.com, that recent sunspot, though very
short lived, was a new Solar Cycle 25 spot:

https://bit.ly/2KJ7cyy

Average daily solar flux this week dipped slightly from 70.3 to
69.9. Geomagnetic conditions were quiet, with average daily
planetary A index receding marginally from 4 to 3.6, and average
mid-latitude A index going from 3 to 2.3.

Predicted solar flux is 70 on November 22-23, 68 on November 24 then
67 on November 25-28, 69 on November 29 through December 8, 70 on
December 9-22, and then 69 on December 23 through January 4 and 70
on January 5.

Predicted planetary A index is 16, 10 and 8 on November 22-24, 5 on
November 25 through December 12, 6 on December 13, 5 on December
14-15, then 8, 15, 20, 18 and 10 on December 16-20, 8 on December
21-23, and 5 on December 24 to January 4.

Geomagnetic activity forecast for the period November 22 til
December 17, 2019 from OK1HH.

"Geomagnetic field will be:
Quiet on: November 29-30, December 1, 10-16 
Quiet to unsettled on: November 27-28, December 2, 7-9, 17
Quiet to active on: November (25-26,) December 3-6
Unsettled to active on: November 23 (-24) 
Active to disturbed: November (22)

"Solar wind will intensify on: November 22-24, (25-26) December (3-9,
13-14,) 16-17.

"Parenthesis means lower probability of activity enhancement."

ND4DX shared:

"Your comment of how amazing long distant contacts are still
possible with present conditions brought back memories of the VP6DX
expedition to Ducie Island 11 years ago during another solar minimum, I
was able to work them SSB on all phone bands, 80-10 w/100w mobile
with hustler/hamsticks. I'll bet if I looked through the log at
other solar minimums I'd see similar results. So I think all this
worry folks have over the solar minimum is all nonfounded, sure the
sunspots make it easier. But now it is even more challenging and
interesting with pretty much the same results as I've found now with
the 100w and a 43' vertical, and NO FT8.

"73 es DX Fred ND4DX."

David P. Moore sent two articles on solar physics:

https://bit.ly/2KL6sJk

https://bit.ly/2XzVBqS

Dr. Tamitha Skov, WX6SWW gives us a timely forecast:

https://youtu.be/WrIsipdOfF0

Here is an interesting resource from Japan, showing daily sunspot
data beginning in 1929:

https://solarwww.mtk.nao.ac.jp/en/db_sunspot.html

This weekend is the CW portion of the CQ Worldwide DX Contest:

https://www.cqww.com/

If you would like to make a comment or have a tip for our readers,
email the author at, k7ra@arrl.net.

For more information concerning radio propagation, see the ARRL
Technical Information Service web page at.
http://arrl.org/propagation-of-rf-signals. For an explanation of
numbers used in this bulletin, see
http://arrl.org/the-sun-the-earth-the-ionosphere.

An archive of past propagation bulletins is at
http://arrl.org/w1aw-bulletins-archive-propagation. More good
information and tutorials on propagation are at http://k9la.us/.

Monthly propagation charts between four USA regions and twelve
overseas locations are at http://arrl.org/propagation.

Instructions for starting or ending email distribution of ARRL
bulletins are at http://arrl.org/bulletins.

Sunspot numbers for November 14 through 20, 2019 were 0, 0, 0, 0, 0,
0, and 0, with a mean of 0. 10.7 cm flux was 69.9, 70, 69.7, 70.1,
70.4, 69.2, and 70.2, with a mean of 69.9. Estimated planetary A
indices were 4, 4, 6, 5, 2, 2, and 2, with a mean of 3.6. Middle
latitude A index was 3, 2, 5, 3, 1, 1, and 1, with a mean of 2.3.
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/EX