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ARRL Propagation Bulletin ARLP046 (2016)

SB PROP @ ARL $ARLP046
ARLP046 Propagation de K7RA

ZCZC AP46
QST de W1AW  
Propagation Forecast Bulletin 46  ARLP046
From Tad Cook, K7RA
Seattle, WA  November 11, 2016
To all radio amateurs 

SB PROP ARL ARLP046
ARLP046 Propagation de K7RA

At 0002 UTC on November 9, this geomagnetic warning was distributed
by Australia's Space Forecast Centre:

"SUBJ: SWS GEOMAGNETIC DISTURBANCE WARNING 16/48 ISSUED AT 0002UT/09
NOVEMBER 2016 BY THE AUSTRALIAN SPACE FORECAST CENTRE.

"INCREASED GEOMAGNETIC ACTIVITY EXPECTED DUE TO CORONAL HOLE HIGH
SPEED WIND STREAM AND POSSIBLE GLANCING BLOW FROM CME ASSOCIATED
WITH 05NOV FILAMENT ON 09-10 NOVEMBER 2016

"GEOMAGNETIC ACTIVITY FORECAST
09 Nov:  Quiet to Minor Storm
10 Nov:  Active"

Later on the same day, the USAF Space Weather operation Ap forecast
predicts the disturbance perhaps a few days later. The USAF forecast
was issued about 21 hours later than the Australian forecast. Now we
have an updated forecast from Thursday, November 10.

At 0005 UTC on November 11 a similar warning was issued:

"INCREASED GEOMAGNETIC ACTIVITY EXPECTED DUE TO CORONAL HOLE HIGH
SPEED WIND STREAM FROM 11-12 NOVEMBER 2016.

"GEOMAGNETIC ACTIVITY FORECAST
11 Nov:  Unsettled with possible Active to Minor Storm periods
12 Nov:  Active to Minor Storm"

Average daily sunspot number over the past week (November 3-9)
doubled from 9.1 to 18.7, compared to the previous seven days.
Average daily solar flux changed only marginally from 77.5 to 76.9.
Geomagnetic indices were lower, with average planetary A index
changing from 18.1 to 6.4, and mid-latitude A index (measured at
Wallops Island, Virginia) moved from 13.4 to 4.3.

Predicted planetary A index is 26, 28, 18 and 12 on November 11-14,
then 8, 5, 3 and 5 on November 15-18, then 8, 15, 54, 42 and 24 on
November 19-23, then 18, 22, 18, 12 and 10 on November 24-28, 8 on
November 29-30, 5 on December 1-3, then 8, 20 and 8 on December 4-6,
10, 12 and 20 on December 7-9, then 18, 10 and 8 on December 10-12,
5 on December 13-15, then 8, 15, 54, 42 and 24 on December 16-20,
and 18, 22 and 18 on December 21-23.

Predicted solar flux is 80 on November 11-13, 85 on November 14-15,
90 on November 16-17, then 80, 77 and 75 on November 18-20, 78 on
November 21-22, 79 on November 23-25, 78 on November 26, 77 on
November 27-28, 76 on November 29-30, 77 on December 1-3, 75 on
December 4-5, then 78 on December 6-15, 77 and 75 on December 16-17,
then 78 on December 18-19 and 79 on December 20-22.

F.K. Janda, OK1HH of the Czech Propagation Interest Group sends us
this geomagnetic activity forecast for the period November
11-December 7, 2016.

Geomagnetic field will be:
Quiet on November 15-17, December 1-4
Mostly quiet on November 14, 19, 28, December 7
Quiet to unsettled on November 11, 18, 26-27, December 5
Quiet to active on November 12-13, 20, 24, 29-30, December 6
Active to disturbed on November 21-22, (23, 25)

Increased solar wind from coronal holes are expected on November
11-13, 18-20

Remark: - Parenthesis means lower probability of activity
enhancement. - Reliability of predictions is reduced at present.

Jeff Hartley, N8II of Shepherdstown, West Virginia checked in with
observations on November 10:

"Nothing too exciting has happened on the bands until today. SFI has
been running around 76-78 most of the week with quiet geomagnetic
conditions, but the limited daylight now is really limiting polar
path DX with just a few JAs and R0XR in Eastern Asiatic Russia
logged on 20 around 2300Z.

"Signals are good from Australia most mornings around 1230Z on 20
meters. 15 meters is open most days to the Mediterranean area of EU
extending up to England with some strong signals from that area.
Today, Nov 10, was pretty typical with signals improving around
1600Z to EU with Peter, MI1ERL in Northern Ireland being the loudest
worked at S9+20dB on peaks. I then checked 12 meter CW to find ZD8W
on Ascension Island in the south Atlantic with a Spanish station
heard calling him. I logged ZD8W, then proceeded to work several
Spanish stations with good signals along with two from Portugal
including CT1DGE running 5 watts. EA8DO and EA8TL in the Canary Is.
were both S9+. But the big surprise of the day was a call from
Finland, OH2LZC at 1639Z, also on 12 meters. There must have been
some auroral Es, Niko was only running 200W to an 80M loop antenna
and was S5 on peaks with deep rapid QSB."

Ran across this interesting piece today about reconstructing sunspot
data from 400 years ago:

http://bit.ly/2fpj8EK

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 3 through 9 were 23, 25, 24, 23, 24, 0,
and 12, with a mean of 18.7. 10.7 cm flux was 75.6, 76.7, 76.7,
76.2, 76.5, 76.9, and 79.9, with a mean of 76.9. Estimated planetary
A indices were 18, 5, 3, 5, 4, 3, and 7, with a mean of 6.4.
Estimated mid-latitude A indices were 12, 3, 2, 4, 2, 2, and 5, with
a mean of 4.3.
NNNN
/EX