SB PROP @ ARL $ARLP049
ARLP049 Propagation de K7RA

ZCZC AP49
QST de W1AW
Propagation Forecast Bulletin 49  ARLP049
> From Tad Cook, K7RA
Seattle, WA  December 4, 2015
To all radio amateurs

SB PROP ARL ARLP049
ARLP049 Propagation de K7RA

Solar indicators dropped this week, with average daily sunspot numbers at 41.6
from November 26 through December 2, down from 62.7 in the previous seven days.

Average daily solar flux dropped 18 points, from 115.2 to 97.2. A week ago the
predicted average daily solar flux for the same period was 111.4, more than 14
points above the actual outcome.

Average daily planetary A index was 9.9, while average daily mid-latitude A
index was 6.6, more than double the two figures for the previous week, 4.1 and
3.1 respectively. But there were no days
with high geomagnetic activity. The most was on Monday and Tuesday, with
planetary A index at 19 and 14 indicating moderately unsettled conditions.

Predicted solar flux is 95 on December 4, 90 on December 5-8, 95 on December
9-10, 105 on December 11, 115 on December 12-13, then 110, 105 and 100 on
December 14-16, 105 on December 17-18, 110 on
December 19-20, 105 on December 21, and 100 on December 22-26. Following this
coming week the lowest predicted solar flux is on just one day, at 95 on
December 27, five days after the Winter Solstice.

Predicted planetary A index is 8 on December 4-5, then 18, 25, 20 and 15 on
December 6-9, then 8 on December 10-15, then 10 and 8 on December 16-17, 5 on
December 18-23 and 8 on December 24-26. The next period of unsettled to active
geomagnetic conditions is December 28, with a predicted planetary A index of
25. The planetary A index doesn't settle down to 5 again until mid-January.

OK1HH predicts geomagnetic activity will be quiet to unsettled December 4-5,
active to disturbed December 6-8, quiet on December 9, quiet to active December
 10, mostly quiet December 11, quiet to
unsettled December 12-14, quiet to active December 15, mostly quiet December
16, quiet on December 17-23, mostly quiet December 24-25, quiet to active
December 26-27, mostly quiet December 28, active to disturbed December 29, and
back to quiet again on December 30.

He expects an increase in solar wind on December (5-7), 8-10, (11-12, 16-20,)
26-27, and (28-29). He is less certain about heightened activity on the dates
in parenthesis.

Unfortunately, we received no reports on conditions during last weekend's CQ
World-Wide CW DX contest. This weekend is the ARRL 160 Meter contest. This is a
 CW only event, and lasts 42 hours with no time limit from 2200 UTC Friday
(today) to 1600 UTC on Sunday, December 4-6.

See http://www.arrl.org/160-meter for complete details and rules.

With low predicted geomagnetic activity over the weekend, 160 meters should be
in good shape for the contest.

Average daily sunspot number for the month of November was 61.9. For August,
September and October the monthly averages were 61.7, 72.5, and 59.6.

Our three month moving average of daily sunspot numbers, (September 1 through
November 30) was 64.6. For the 3 month periods ending in June through October
the averages were 77.7, 76.3, 69.1, 67.5 and 64.5. At the cycle's peak, for
periods ending in March and April of 2014, the 3 month moving averages were
146.4 and 148.2. It's been a pretty steady decrease since then, with the
averages dropping below 100 at the beginning of this year.

Don Anderson, N7EF of Kent, Washington sends this video about a 2018 space
mission all the way to the Sun:  http://on.wsj.com/1l5FZHr

Andrew Gudas, N7TP of Amargosa Valley, Nevada sends along this story about
scary superflares: http://bit.ly/21AsfVJ

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

My own archives of the NOAA/USAF daily 45 day forecast for solar flux and
planetary A index are in downloadable spreadsheet format at
http://bit.ly/1VOqf9B and http://bit.ly/1DcpaC5 .

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 http://arrl.org/propagation.

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

Sunspot numbers for November 26 through December 2 were 56, 48, 36, 47, 51, 27,
 and 26, with a mean of 41.6. 10.7 cm flux was 103.9, 98.9, 96.6, 95.5, 95.7,
94.6, and 95.3, with a mean of 97.2. Estimated planetary A indices were 3, 7,
8, 9, 19, 14, and 9, with a mean of 9.9. Estimated mid-latitude A indices were
2, 4, 5, 7, 10, 11, and 7, with a mean of 6.6.

NNNN
/EX

)\/(ark

"So let me ask you a question about this brave new world of yours. When you've
killed all the bad guys, and when it's all perfect, and just and fair, and when
 you have finally got it exactly the way you want it, what are you going to do
with the people like you? The trouble makers. How are you going to protect your
 glorious revolution from the next one?"
- The twelfth Doctor

... The golden years are when actions creak louder than words.
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 * Origin:  (1:3634/12.73)