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ARRL Propagation Bulletin ARLP005 (2015)

ARLP005 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 5  ARLP005
From Tad Cook, K7RA
Seattle, WA  January 30, 2015
To all radio amateurs 

ARLP005 Propagation de K7RA

Average daily sunspot numbers for the January 22-28 period rose from
61.9 on the previous seven days to 89.1. Average daily solar flux
rose from 126.2 to 136.8 over the same period.

There were two new sunspot regions on January 22, another one on
January 23 and again on January 25, four more on January 26, another
two on January 28 and one more on January 29.

The average daily solar flux for the following seven days, January
29 through February 4 is predicted to be 163.6, nearly 27 points
higher than the previous week.

Predicted solar flux is 170 on January 30 through February 1, then
165 and 155 on February 2-3, 150 on February 4-5, 140 on February 6,
130 on February 7-9, 125 on February 10-11, 120 on February 12-13,
and 125 on February 14-16. Flux values then reach a low of 115 on
February 18, then a high of 135 on February 26-28.

Predicted planetary A index is 15 on January 30 through February 1,
12 on February 2, 10 on February 3-7, 8 on February 8-9, 5 on
February 10-14, 12 on February 15, and 10 on February 16-18.

F.K. Janda, OK1HH blesses us with his geomagnetic prediction from
the Czech Propagation Interest Group. He sees quiet to unsettled
conditions January 30, disturbed conditions January 31, active to
disturbed February 1, quiet to active February 2, disturbed on
February 3, mostly quiet on February 4, quiet to unsettled February
5, quiet to active February 6, active to disturbed February 7, quiet
on February 8, mostly quiet February 9-15, quiet on February 16,
quiet to active February 17, mostly quiet February 18-19, quiet on
February 20, mostly quiet February 21, quiet to active February
22-23, active to disturbed February 24, disturbed on February 25.

OK1HH expects an increase (he calls it an amplification) of solar
wind on February 3-4, 19-20, and 25. Also note that OK1HH refers to
the "Czech Propagation Interested Group," but I suspect that
"interest group" is probably a better translation to American

Mike Gilmer, N2MG of Vernon, New York found a bad URL in some
versions of last week's Propagation Forecast Bulletin ARLP004.

The correct URL for the Wikipedia list of solar cycles is:

Somehow a .png extension was added to the bulletin in the W1AW
archive and the one that was emailed to readers.  But the link from
the ARRL home page had the correct URL:

The bulletin in the archive has been updated.

Dick Bingham, W7WKR, who lives way off the grid in North Central
Washington State, sends this article about experimental licenses
granted by the FCC.

We received no reports from readers this week about propagation or
on the air activity.

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

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 January 22 through 28 were 63, 70, 57, 65, 110,
119, and 140, with a mean of 89.1. 10.7 cm flux was 120.3, 121.1,
125.3, 126.6, 147, 158.1, and 159.3, with a mean of 136.8. Estimated
planetary A indices were 12, 9, 7, 6, 16, 12, and 7, with a mean of
9.9. Estimated mid-latitude A indices were 9, 8, 5, 3, 12, 9, and 5,
with a mean of 7.3.


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