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ARRL Propagation Bulletin ARLP047 (2016)

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 18, 2016
To all radio amateurs 

SB PROP ARL ARLP047
ARLP047 Propagation de K7RA

Solar flux and sunspot numbers moved in opposite directions over the
past week, and differences were more extreme than usual. Normally we
expect daily sunspot numbers and solar flux to track together, and
geomagnetic indices to track with each other as well, at least
approximately.

Average daily sunspot numbers over the past reporting week (November
10-16) rose 10 points from 18.7 to 28.7, while average daily solar
flux dropped from 76.9 to 45.8. These comparisons express
differences from the previous reporting week, November 3-9.

Over the same dates average planetary A index increased markedly
from 6.4 to 12.7, while the mid-latitude A index changed from 4.3 to
10.1.

Predicted solar flux values for the near future are 79 on November
18, 78 on November 19, 80 on November 20-21, 78 on November 22-26,
80 on November 27, 82 on November 28 through December 1, 84 on
December 2, 82 on December 3-7, 80 on December 8-9, 78 on December
10, 75 on December 11-15, 77 on December 16, 75 on December 17-21
and 78 on December 22-23.

The predicted planetary A index is 5, 16 and 18 on November 18-20,
then 10, 48, 48, 36, and 28 on November 21-24, then 25, 18, 12, 10
and 8 on November 23-29, then 5 on November 30 til December 6, then
15, 12, 18, 20, 15 and 10 on December 7-12 and 5 on December 13-15,
then 10, 15, 55, 45, and 25 on December 16-20, then 18, 25, 18, 12,
10 and 8 on December 21-26, and 5 over the following week.

http://www.spaceweather.com reports the solar cycle is currently at
the lowest level in 5 years.

The ARRL Phone Sweepstakes is this weekend.

An expansion of Space Weather Services was announced at:

http://bit.ly/2fk4Mot

Thanks to Max White and David Moore for the above tip.

Petr Kolman, OK1MGW of the Czech Propagation Interest Group sent his
geomagnetic activity forecast for the period November 18 to December
14, 2016.

Geomagnetic field will be: Quiet on December 2-4, 13-14 Mostly quiet
on November 18, December 1, 12 Quiet to unsettled on November 19,
27-30, December 5-6, 11 Quiet to active on November 20, 24, December
7-10 Active to disturbed on November 21-23, (25-26)

Amplifications of the solar wind from coronal holes are expected on
November 20-26, December 7-10.

Parenthesis means lower probability of activity enhancement.

Jeff, N8II in West Virginia reports, "Saturday, November 12 I was
able to work 24 each OK/OM Czech/Slovak stations on 15 meter CW
(1352-1534Z) and 80 M in a non-serious contest effort (with 100W).
On 15, I only worked one weak Slovak, but some Czechs were loud,
very selective! Sunday, the contest was over at 1200Z and the 15 M
band did not open east of Italy. I made the most QSOs on 20 with
good conditions, but central EU closes early with the time of year
and low SFI. 40 fades down quickly to EU after sunset.

"I just worked V63GW Micronesia with a good signal on 20M CW short
path at 2032Z, expected him to be LP.

"Burma is now QRV and so far nil as expected in WV, best hope is 20
or 30M.

"Wednesday night, November 16 I worked ZD8W Ascension Island on 30
CW around 0100Z with S5-7 signal.

"Thursday 15 M was open as far north as northern Germany (Hanover)
and I easily broke a EU pile up on FR4QF on Reunion Island on 15 SSB
at 1522Z; he was peaking S9."

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 the
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 10 through 16 were 13, 26, 51, 38, 26,
29, and 18, with a mean of 28.7. 10.7 cm flux was 80.2, 78.4, 78.4,
77.8, 77.3, 76.5, and 80.9, with a mean of 45.8. Estimated planetary
A indices were 14, 13, 19, 21, 11, 7, and 4, with a mean of 12.7.
Estimated mid-latitude A indices were 11, 10, 13, 19, 8, 7, and 3,
with a mean of 10.1.
NNNN
/EX