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ARRL Propagation Bulletin ARLP002 (2017)

SB PROP @ ARL $ARLP002
ARLP002 Propagation de K7RA

ZCZC AP02
QST de W1AW  
Propagation Forecast Bulletin 2  ARLP002
From Tad Cook, K7RA
Seattle, WA  January 13, 2017
To all radio amateurs 

SB PROP ARL ARLP002
ARLP002 Propagation de K7RA

No sunspots were visible on January 1-2 and none on January 4-11.
Our reporting week is January 5-11, so the average daily sunspot
number for that period was zero.

For a look at recent sunspot numbers, check
ftp://ftp.swpc.noaa.gov/pub/indices/DSD.txt and note the many
zeroes.

Average daily solar flux this week was 72.5, down from 73.1 the week
before. Average planetary A index rose 5 points to 14.3, while
average mid-latitude A index increased from 6.3 to 10.6.

Predicted solar flux is 80 and 82 on January 13-14, 85 on January
15-19, 76 on January 20-25, 74 on January 26-28, 73 on January 29
through February 1, 72 on February 2-7, 74 on February 8, and 76 on
February 9-21.

Predicted planetary A index is 8 on January 13-14, 5 on January 15,
10 on January 16, 20 on January 17-19, 18 on January 20, 20 on
January 21-22, 10 on January 23, 5 on January 24-26, then 12, 15, 7,
10 and 12 on January 27-31, then 16, 18, 20, 16, 12 and 5 on
February 1-6, then 12, 15, 10 and 8 on February 7-10, 5 on February
11-12, then 25, 20, 25 and 18 on February 13-16, and 20 on February
17-18.

This from "Sky and Telescope" regarding our spotless Sun:

http://www.skyandtelescope.com/astronomy-news/the-spotless-sun/

And, another:

https://www.sott.net/article/339435-Sunspots-vanish-space-weather-continues

From Jon Jones, N0JK:

"Good sporadic-E on 6 meters January 8, 9 and 10th, 2017.

"Best probably day so far January 9, 6 meters was open from coast to
coast with some double hop Es worked from the west coast to 8 land
confirmed by this spot:

"W6XK  17/01/09 1958Z  50276.0 EN81LI CM97 Copied in OH  N8EHW

"K7JA DM03 notes 10 hours of sporadic-E on 6 meters, Jan. 9.

"December, 2016 was so poor. Not sure yet why January, 2017 is so
much better, but will roll with it.

"I worked AI1K DM34 and KA7JOI DM54 with just a 10 W SSB MFJ-9406,
and mag mount whip on the car from the KC VA Hospital parking lot on
a short break from work about 1850z Jan. 9. Both stations were very
strong via sporadic-E on 6. KA7JOI so loud he sounded like was just
a few cars away!  K5SW observed Jan. 9 was 'like summer E-skip on
6."'

NASA released an update on the current solar cycle, but there is no
new information, except two links.

https://solarscience.msfc.nasa.gov/predict.shtml

The updated links:

https://www.nasa.gov/multimedia/videogallery/index.html?media_id=19197261

https://solarprobe.gsfc.nasa.gov/

From OK1HH, F.K. Janda:

"Geomagnetic activity forecast for the period January 13 to February
8, 2017:

"Geomagnetic field will be:
Quiet on January 16, 26
Mostly quiet on January 13, 24-25
Quiet to unsettled on January 14-15, 23, 29, 31, February 5
Quiet to active on January 17, 20, 22, 27, 30, February 3-4, 6, 8
Active to disturbed on January 18-19, 21, 28, February 1-2, 7

"Amplifications of the solar wind from coronal holes are expected on
January 18-20, (21-24,) 26, (31,) February (1-5,) 6-7

"Remark: - Parenthesis means lower probability of activity
enhancement. - Observed indicia of upcoming MAJOR CHANGES in solar
activity!  Therefore, the current forecast is less reliable.

"Beware of 'Paraskavedekatriaphobia' tomorrow. "

I am particularly pleased to see the OK1HH warning about
Paraskavedekatriaphobia - the fear of Friday the 13 - something we
don't hear much about anymore.

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 January 5 through 11, 2017 were 0, 0, 0, 0, 0,
0, and 0, with a mean of 0. 10.7 cm flux was 73.3, 72, 72, 71.5,
71.2, 72.7, and 74.5, with a mean of 72.5. Estimated planetary A
indices were 18, 16, 20, 16, 12, 10, and 8, with a mean of 14.3.
Estimated mid-latitude A indices were 15, 14, 14, 11, 8, 5, and 7,
with a mean of 10.6.
NNNN
/EX