ARRL Propagation Bulletin

Accessed on 17 November 2018, 0509 UTC, Post 770.


Here is the latest propagation forecast compiled by Tad Cook (K7RA) and his volunteer staff of experts and reporters.  In this report, Tad offers a variety of links and other suggestions to help you better understand the dynamics of HF propagation.  This is a “must have” document for those involved in DX operations and contesting.

ARLP046 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 46  ARLP046
From Tad Cook, K7RA
Seattle, WA  November 16, 2018
To all radio amateurs 

ARLP046 Propagation de K7RA

A single sunspot appeared on November 13-14, yielding a daily
sunspot number of 11 over both days. The sunspot number increased to
13 on the following day, November 15. The average daily sunspot
number for the reporting week (November 8-14) was 3.1, after no
sunspots during the previous seven days.

Average daily solar flux rose from 67.7 to 68.5.  Average daily
planetary A index declined from 12 to 8.1, while average
mid-latitude A index shifted from 8.1 to 6.3.

There were no sunspots for 26 days, from October 18 to November 12.

Does this place us near the bottom of the sunspot cycle? Perhaps, or
somewhere toward it. Look at sunspot numbers in 2008-2009, during
the last solar minimum, and note the long periods with no sunspots:

Predicted solar flux over the next 45 days is 68 on November 16
through December 2, 69 on December 3-4, then 70, 69 and 69 on
December 5-7, then 70 on December 8-15, 69 on December 16, then 68
on December 17-29 and 69 on December 30.

Predicted planetary A index is 5 on November 16-17, 8 on November
18, 5 on November 19-24, 8 on November 25, 5 on November 26-30, then
15 and 30 on December 1-2, 10 on December 3-4, 8 on December 5-6, 12
on December 7-9, then 10 and 8 on December 10-11, 5 on December
12-27, then 15, 30 and 10 on December 28-30. reported November 15-16 a geomagnetic unrest
prediction for November 18 or 19, although that is not reflected in
the forecast in the above paragraph. But the OK1HH forecast below
seems to agree with in this regard.

Geomagnetic activity forecast for the period November 16 through
December 12, 2018 from F.K. Janda, OK1HH.

"Geomagnetic field will be:
Quiet on November 16, 19, 26, 29-30, December 11-12
Quiet to unsettled on November 17, 20-21, 24, December 10
Quiet to active on November 22-23, 25, December 4-9
Unsettled to active on November 18, 27-28, December 1, 3
Active to disturbed on December 2

"Solar wind will intensify on November (17-23, 30) and on December
1-3, (4-6,) 7-9, (10)

"Parenthesis means lower probability of activity enhancement."

Steve Sacco, NN4X in Florida reported a Wednesday morning (November
14) 10 meter opening to Europe using FT8.

Max White, M0VNG sent this article about the STEREO mission and
observing comet tails:

K6TW sent info about a massive solar storm in August 1972 which
triggered explosive mines laid in the sea off Vietnam:

W7WKR sent additional info on the same story:

The ARRL SSB Sweepstakes contest is this weekend. See for details.

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
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 November 8 through 14, 2018 were 0, 0, 0, 0, 0,
11, and 11, with a mean of 3.1. 10.7 cm flux was 69.5, 68.9, 69,
69.3, 68.2, 67, and 67.9, with a mean of 68.5. Estimated planetary A
indices were 11, 10, 13, 7, 9, 4, and 3, with a mean of 8.1.
Estimated mid-latitude A indices were 12, 6, 10, 5, 6, 3, and 2,
with a mean of 6.3.